Urbana, IL, United States

The University of Illinois at Urbana–Champaign is a public research-intensive university in the U.S. state of Illinois. A land-grant university, it is the flagship campus of the University of Illinois system. The University of Illinois at Urbana–Champaign is the second oldest public university in the state , and is a founding member of the Big Ten Conference. It is a member of the Association of American Universities and is designated as a RU/VH Research University . The campus library system possesses the second-largest university library in the United States after Harvard University.The university comprises 17 colleges that offer more than 150 programs of study. Additionally, the university operates an extension that serves 2.7 million registrants per year around the state of Illinois and beyond. The campus holds 647 buildings on 4,552 acres in the twin cities of Champaign and Urbana ; its annual operating budget in 2011 was over $1.7 billion. Wikipedia.


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Patent
The Regents Of The University Of Colorado and University of Illinois at Urbana - Champaign | Date: 2016-05-18

The methods and apparatus of the present invention allow the evaluation of inflammation of the esophagus. Measurements may be utilized, for example, to diagnose a disease of the esophagus, to monitor inflammation of the esophagus, or to access the treatment of a disease of the esophagus. In one embodiment, the invention comprises a method for measuring esophageal inflammation comprising deploying a device into the esophagus of a subject, removing the device after a predetermined period of time, analyzing the device for a diagnostic indicator of esophageal inflammation and evaluating the diagnostic indicator to diagnose esophageal inflammation.


Patent
University of Illinois at Urbana - Champaign, Vanquish Oncology and Johns Hopkins University | Date: 2016-08-22

The invention provides compositions and methods for the induction of cell death, for example, cancer cell death. Combinations of compounds and related methods of use are disclosed, including the use of compounds in therapy for the treatment of cancer and selective induction of apoptosis in cells. The disclosed drug combinations can have lower neurotoxicity effects than other compounds and combinations of compounds.


Patent
H. Lee Moffitt Cancer Center, Research Institute and University of Illinois at Urbana - Champaign | Date: 2016-08-08

Disclosed are selective histone deactylase inhibitors (HDACi) that having Formula (I). Methods of making and using these inhibitors for the treatment of cancer, in particular melanoma are also disclosed.


Patent
University of Illinois at Urbana - Champaign | Date: 2016-08-29

A chamber for a cell culture and a chamber holder system are disclosed. A representative chamber embodiment includes a first layer; and a second layer coupled to the first layer, the second layer further comprising a well having at least one side wall, the well extending through the second layer, wherein a predetermined portion of the first layer is substantially optically transmissive and is exposed in and forms a lower side of the well. The well may have a laminar flow shape, and may also include a plurality of recesses to accommodate the tips of inflow and outflow devices, such as for superfusion applications. The second layer may be comprised of a hydrophobic material or comprised of a material having a lower density than the density of culture medium to provide a buoyant chamber for sandwich cell cultures, along with submersible chambers.


Patent
University of Illinois at Urbana - Champaign | Date: 2015-05-15

Disclosed is a derivative of amphotericin B (AmB), denoted C2epiAmB, with an improved therapeutic index over amphotericin B, pharmaceutical compositions comprising the AmB derivative, methods of making the AmB derivative and the pharmaceutical composition, and their use in methods of inhibiting growth of a yeast or fungus and treating a yeast or fungal infection. C2epiAmB is an epimer of the parent compound. Specifically, C2epiAmB differs from the parent compound at the CT stereogenic center on mycosamine. This difference in structure results in (i) retained capacity to bind ergosterol and inhibit growth of yeast, (ii) greatly reduced capacity to bind cholesterol, and (iii) essentially no toxicity to human cells.


Patent
University of Illinois at Urbana - Champaign | Date: 2016-09-23

Autonomic cooling of a substrate is achieved using a porous thermal protective layer to provide evaporative cooling combined with capillary pumping. The porous thermal protective layer is manufactured onto the substrate. A vascular network is integrated between the substrate and the protective layer. Applied heat causes fluid contained in the protective layer to evaporate, removing heat. The fluid lost to evaporation is replaced by capillary pressure, pulling fluid from a fluid-containing reservoir through the vascular network. Cooling occurs as liquid evaporates from the protective layer.


Patent
University of Illinois at Urbana - Champaign, Rohm, Haas Electronic Materials LLC and Dow Chemical Company | Date: 2016-03-10

In one aspect, structures are provided that comprise (a) a one-dimensional periodic plurality of layers, wherein at least two of the layers have a refractive index differential sufficient to provide effective contrast; and (b) one or more light-emitting nanostructure materials effectively positioned with respect to the refractive index differential interface, wherein the structure provides a polarized output emission.


Patent
University of Illinois at Urbana - Champaign | Date: 2016-09-28

A system and method includes nano opto-mechanical-fluidic resonators (nano-resonators), e.g., for identification of particles, e.g., single viruses and/or cells.


Patent
University of Illinois at Urbana - Champaign | Date: 2016-09-28

A system and method includes resonator device to detect cells or other particles through light and/or vibration sensing.


Patent
University of Illinois at Urbana - Champaign | Date: 2016-11-11

A magnetically driven micropump for handling small fluid volumes. The micropump includes a first chamber and a second chamber. A flexible membrane being disposed between the first and second chambers. The flexible membrane being magnetically coupled to an actuator for displacing the membrane.


Patent
University of Illinois at Urbana - Champaign | Date: 2015-11-17

Methods and apparatus for storing information or energy. An array of nano-capacitors is provided, where each nano-capacitor has a plurality of cathodic regions and an anode separated from each of the cathodic regions by one or more intervening dielectrics. Each nano-capacitor acts as a quantum resonator thereby suppressing electron emission. The thickness of the intervening dielectric is in the range between 0.1 nanometers and 1000 nanometers and is shorter than an electron mean free path within the dielectric. Each cathodic region is at least 100 times larger than the thickness of the intervening dielectric in every direction transverse to the thickness of the intervening dielectric. An excess of electrons is stored on the cathodic regions. The dielectric may be a metal oxide, particularly a native oxide of the cathode material.


Patent
University of Illinois at Urbana - Champaign | Date: 2016-08-23

Compositions are provided comprising water-stable semi-conductor nanoplatelets encapsulated in a hydrophilic coating further comprising lipids and lipoproteins. Uses include biomolecular imaging and sensing, and methods of making comprise: colloidal synthesis of CdSe core NPLs; layer-by-layer growth of a CdS shell; and encapsulation of CdSe/CdScore/shell NPLs in lipid and lipoprotein components through an evaporation-encapsulation using zwitterionic phospholipids, detergents, and amphipathic membrane scaffold proteins.


Tietz J.I.,University of Illinois at Urbana - Champaign
Nature Chemical Biology | Year: 2017

Ribosomally synthesized and post-translationally modified peptide (RiPP) natural products are attractive for genome-driven discovery and re-engineering, but limitations in bioinformatic methods and exponentially increasing genomic data make large-scale mining of RiPP data difficult. We report RODEO (Rapid ORF Description and Evaluation Online), which combines hidden-Markov-model-based analysis, heuristic scoring, and machine learning to identify biosynthetic gene clusters and predict RiPP precursor peptides. We initially focused on lasso peptides, which display intriguing physicochemical properties and bioactivities, but their hypervariability renders them challenging prospects for automated mining. Our approach yielded the most comprehensive mapping to date of lasso peptide space, revealing >1,300 compounds. We characterized the structures and bioactivities of six lasso peptides, prioritized based on predicted structural novelty, including one with an unprecedented handcuff-like topology and another with a citrulline modification exceptionally rare among bacteria. These combined insights significantly expand the knowledge of lasso peptides and, more broadly, provide a framework for future genome-mining efforts. © 2017 Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved.


Lewis C.J.T.,University of Illinois at Urbana - Champaign
Nature Reviews Molecular Cell Biology | Year: 2017

An emerging body of evidence indicates that post-transcriptional gene regulation relies not only on the sequence of mRNAs but also on their folding into intricate secondary structures and on the chemical modifications of the RNA bases. These features, which are highly dynamic and interdependent, exert direct control over the transcriptome and thereby influence many aspects of cell function. Here, we consider how the coupling of RNA modifications and structures shapes RNA–protein interactions at different steps of the gene expression process. © 2017 Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved.


Koiliaris K.,University of Illinois at Urbana - Champaign | Xu C.,University of Illinois at Urbana - Champaign
Proceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms | Year: 2017

Given a multiset S of n positive integers and a target integer t, the subset sum problem is to decide if there is a subset of S that sums up to t. We present a new divide-and-conquer algorithm that computes all the realizable subset sums up to an integer u in where is the sum of all elements in S and eO hides polylogarithmic factors. This result improves upon the standard dynamic programming algorithm that runs in O(nu) time. To the best of our knowledge, the new algorithm is the fastest general deterministic algorithm for this problem. We also present a modified algorithm for finite cyclic groups, which computes all the realizable subset sums within the group in time, where m is the order of the group. Copyright © by SIAM.


Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics. "The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including biological and structural health monitoring sensors," explained Sameh Tawfick, an assistant professor of mechanical science and engineering at Illinois. "Aligned carbon nanotube sheets are suitable for a wide range of application spanning the micro- to the macro-scales including Micro-Electro-Mechanical Systems (MEMS), supercapacitor electrodes, electrical cables, artificial muscles, and multi-functional composites. "To our knowledge, this is the first study to apply the principles of fracture mechanics to design and study the toughness nano-architectured CNT textiles. The theoretical framework of fracture mechanics is shown to be very robust for a variety of linear and non-linear materials." Carbon nanotubes, which have been around since the early nineties, have been hailed as a "wonder material" for numerous nanotechnology applications, and rightly so. These tiny cylindrical structures made from wrapped graphene sheets have diameter of a few nanometers--about 1000 times thinner than a human hair, yet, a single carbon nanotube is stronger than steel and carbon fibers, more conductive than copper, and lighter than aluminum. However, it has proven really difficult to construct materials, such as fabrics or films that demonstrate these properties on centimeter or meter scales. The challenge stems from the difficulty of assembling and weaving CNTs since they are so small, and their geometry is very hard to control. "The study of the fracture energy of CNT textiles led us to design these extremely tough films," stated Yue Liang, a former graduate student with the Kinetic Materials Research group and lead author of the paper, "Tough Nano-Architectured Conductive Textile Made by Capillary Splicing of Carbon Nanotubes," appearing in Advanced Engineering Materials. To our knowledge, this is the first study of the fracture energy of CNT textiles. Beginning with catalyst deposited on a silicon oxide substrate, vertically aligned carbon nanotubes were synthesized via chemical vapor deposition in the form of parallel lines of 5?μm width, 10?μm length, and 20-60?μm heights. "The staggered catalyst pattern is inspired by the brick and mortar design motif commonly seen in tough natural materials such as bone, nacre, the glass sea sponge, and bamboo," Liang added. "Looking for ways to staple the CNTs together, we were inspired by the splicing process developed by ancient Egyptians 5,000 years ago to make linen textiles. We tried several mechanical approaches including micro-rolling and simple mechanical compression to simultaneously re-orient the nanotubes, then, finally, we used the self-driven capillary forces to staple the CNTs together." "This work combines careful synthesis, and delicate experimentation and modeling," Tawfick said. "Flexible electronics are subject to repeated bending and stretching, which could cause their mechanical failure. This new CNT textile, with simple flexible encapsulation in an elastomer matrix, can be used in smart textiles, smart skins, and a variety of flexible electronics. Owing to their extremely high toughness, they represent an attractive material, which can replace thin metal films to enhance device reliability." In addition to Liang and Tawfick, co-authors include David Sias and Ping Ju Chen.


News Article | May 2, 2017
Site: www.eurekalert.org

Research at the University of Illinois at Urbana-Champaign has provided the first evidence that viruses and hosts share highly similar regulatory sequences in their promoters--the initiation sequences of human genes that code for functional proteins. "To date viral-host networks include protein and mRNA interactions between viruses and their hosts at later stages of gene expression, but our discovery of genetically coupled promoters is novel. They present an additional layer of regulatory synchrony between virus and host, established and poised before either expresses their protein products," explained Roy Dar, an assistant professor of bioengineering at Illinois. Latent or dormant HIV infected cell reservoirs have been identified as the major barrier towards a cure due to their ability to spontaneously reactivate after removal of antiretroviral therapy. Leading strategies for eradication of HIV attempt to reactivate the whole latent reservoir and clear it with current drug cocktails, a process referred to as 'shock and kill' therapy. "Promoters of genes coded within our DNA and the HIV-1 viral promoter which initiates active replication of the virus are strongly coupled in their regulation leading to co-expression--potentially for a viral fitness advantage. In this study, we investigated a specific T-cell migratory pathway that HIV has coupled to, gaining therapeutic insights currently unknown to the HIV cure research community," Dar added. Promoter similarity of human immunodeficiency virus (HIV) and a human surface receptor allows shared activators to co-regulate viral-host gene expression (blue and red in the cell nucleus). Viral proteins bind cell surface receptors enabling viral control of host cell migration (right side). Those same viral proteins form viral offspring which are shed from the host cell and increase infectious risk to the moving cell's environment. Promoter similarity of human immunodeficiency virus (HIV) and a human surface receptor allows shared activators to co-regulate viral-host gene expression (blue and red in the cell nucleus). Viral proteins bind cell surface receptors enabling viral control of host cell migration (right side). Those same viral proteins form viral offspring which are shed from the host cell and increase infectious risk to the moving cell's environment. Within the systems and synthetic biology fields, the group's findings reveal an additional layer of regulation with which viruses co-evolve with coding-genes and interlace pathways in their hosts. "The study also presents a mechanism for synchronizing initiation of gene expression in synthetic gene circuitry," stated Kathrin Bohn-Wippert, a postdoctoral researcher and first author of the paper, "Genetic coupling of viral-host gene expression presents migratory challenges in HIV therapies" (10.1038/NCOMMS15006), appearing in Nature Communications. "Specifically, in this framework of viral-host genetic coupling we found that the HIV and human CXCR4 promoters are co-regulated and co-expressed. CXCR4 is a chemokine receptor involved in one of the major migratory pathways throughout our body." "We have demonstrated, for the first time, that the virus co-expresses with the receptor in order to control infected cell migration and its importance in HIV 'shock and kill' eradication strategies (therapies towards a cure). We also demonstrated how drug treatments can differentially control infected cell migration and/or reactivation of the virus from its latent and inactive state," she said. According to the researchers, additional network mapping of the coevolution of virus and host-cell gene regulatory coupling will guide future therapeutic strategies, expand systems biology efforts on viral-host networks, and provide novel design principles to reverse bioengineer viral circuitry for synthetic biology and gene therapies. "For the HIV Cure Community we hope this study will raise awareness to the added challenges facing leading strategies towards a cure," remarked Dar, who is also affiliated with the Carl R. Woese Institute for Genomic Biology and the Center for Biophysics and Quantitative Biology at Illinois. "We hope this study will provide new insights to exploit viral-host relationships and viral control of cell migration for advanced therapeutic strategies." Co-authors include Melina Megaridis and Erin Tevonian, both bioengineering undergraduate researchers, in the Illinois Cancer Scholars Program, and in the Dar "Noise Biology" Lab.


News Article | April 17, 2017
Site: www.eurekalert.org

The threshold for transitioning students from English learners to fluent English proficient status--a process termed reclassification--varies widely across and within states, finds a study by NYU's Steinhardt School of Culture, Education, and Human Development, Oregon State University, and the University of Illinois at Urbana-Champaign. The findings, published in a special centennial issue of the American Educational Research Journal, inform conversations about statewide policies for English learner reclassification, which are now mandated under the 2015 Every Student Succeeds Act. "Our study examined the effect of state-level decisions as implemented at a local level. With the Every Student Succeeds Act stipulating that reclassification policies be standardized within a state, our work gives a glimpse into what we might see more broadly once these policies are standardized," said Joseph Robinson Cimpian, associate professor of economics and education policy at NYU Steinhardt and the study's lead author. "Notably, our findings revealed a wide array of effects of reclassification on achievement and graduation, ranging from large negative effects in some districts to large positive effects in others, even when considering students subject to the same state-level policies." By 2050, over a third of school-age children in the U.S. are projected to be immigrants or the children of immigrants, and many of these children will be classified as English learners. Effectively educating the large English learner population requires appropriate instructional services and settings throughout the time students are learning English, as well as during their transition to fluent English status. Because reclassification often entails a change in services and settings, it is important that the switch occurs at the appropriate time: when the student no longer receives added benefit from the English learner setting. Reclassification criteria vary across states, districts within a state, and even within districts. However, they all use some determination of whether an English learner is achieving at a pre-specified level on an assessment determined by local policymakers. A recent wave of education research uses a technique known as regression discontinuity designs, which use large amounts of data to compare the outcomes of students who just barely attained the reclassification criteria with those who just barely failed to attain it, helping researchers to understand the effects of reclassification on students with very similar profiles. While previous studies have examined effects within a single school district, the current study is the first to examine reclassification effects across multiple districts and measure variability between them. The researchers used longitudinal data from 107,549 students in two states--one in the Southeast and one in the Northwest--and applied regression discontinuity designs to assess the effects of reclassification on later achievement and graduation. All students studied were at some point considered English learners and were enrolled in elementary, middle, or high school when they were reclassified. The researchers found remarkable variability between districts in how reclassification affected student achievement and graduation rates. In some districts, reclassification had negative effects on graduation, where students who were reclassified but just barely made the cut-off were as much as 80 percent less likely to graduate. Meanwhile, reclassification in other districts had positive effects on graduation. Just-barely reclassified students were 38 percentage points more likely to graduate than peers who stayed in an English learner setting. "This variability tells us that we should not default to a belief that reclassification is universally beneficial or detrimental," said Cimpian. The researchers conclude that this type of research can help policymakers see misalignment between their thresholds for reclassification and the instruction and services in their state and districts. Fixing this misalignment might include lowering or raising the reclassification threshold as well as modifying instruction and services for students near the threshold. For example, if reclassification was found to have a negative effect on student outcomes, a district might consider providing additional language development support for students right after reclassification. Of note, the passing of the Every Student Succeeds Act requires states to establish uniform reclassification criteria for all districts, meaning districts may not have the freedom to adjust their thresholds or add in additional considerations for reclassification. "On one hand, establishing the same criteria has the benefit of facilitating comparisons across districts and providing a common metric by which to assess English learner status for students who move across district boundaries. On the other hand, requiring a common threshold across the state restricts the ability of a district to adjust the threshold to meet the needs of its own students given the services that the district provides," Cimpian said. Commenting on the importance of this research in the American Educational Research Journal, Kenji Hakuta of Stanford University said it is a "wonderful display of the power of combining current analytic methods, present-day educational datasets, practitioner-researcher collaborative arrangements, and key policy questions pertaining to the educational outcomes of English learners. "This paper's important message is that policies and implementation matter at the state and local levels in ways that demonstrably affect the probability of graduation for individual students," Hakuta continued. In addition to Cimpian, authors include Karen D. Thompson of Oregon State University and Martha B. Makowski of the University of Illinois at Urbana-Champaign. This research was funded by a National Academy of Education/Spencer Foundation Postdoctoral Fellowship and a University of Illinois Hardie Fellowship awarded to Cimpian and a U.S. Department of Education Institute of Education Sciences grant (R305H140072) for which Thompson is the principal investigator. About the Steinhardt School of Culture, Education, and Human Development (@nyusteinhardt) Located in the heart of Greenwich Village, NYU's Steinhardt School of Culture, Education, and Human Development prepares students for careers in the arts, education, health, media, and psychology. Since its founding in 1890, the Steinhardt School's mission has been to expand human capacity through public service, global collaboration, research, scholarship, and practice. To learn more about NYU Steinhardt, visit steinhardt.nyu.edu.


News Article | April 24, 2017
Site: www.eurekalert.org

Using an atomic quantum simulator, scientists at the University of Illinois at Urbana-Champaign have achieved the first-ever direct observation of chiral currents in the model topological insulator, the 2-D integer quantum Hall system.


News Article | April 17, 2017
Site: www.newscientist.com

“Sock puppets” are the scourge of online discussion . Multiple accounts controlled by the same user can dominate comment forums and spread fake news. But now there’s a way to unmask the puppeteers. A study of nine websites that use comment service Disqus to let readers post responses to articles found that sock puppets can be identified based on their writing style, posting activity and relationship with other users. In the era of fake news, detecting sock puppets is important, says Srijan Kumar at the University of Maryland. “Whenever multiple accounts are used by the same party it is harmful and it skews the discussion and fake news can be propagated very confidently,” he says. Kumar and his colleagues at the University of Maryland and Stanford University in California analysed commenter accounts on news websites including CNN, NPR, Breitbart and Fox News. They identified the sock puppets by finding accounts that posted from the same IP address in the same discussion at similar times. This approach isn’t always possible, so they wanted to develop a tool that automatically detects sock puppets based only on publicly accessible posting data. They found that sock puppets contribute poorer quality content, writing shorter posts that are often downvoted or reported by other users. They post on more controversial topics, spend more time replying to other users and are more abusive. Worryingly, their posts are also more likely to be read and they are often central to their communities, generating a lot of activity. Based on their findings, the researchers created a machine learning tool that can detect if two accounts belong to the same person 91 per cent of the time. Another tool can distinguish between a regular account and a sock puppet with 68 per cent accuracy. The research will be presented this week at the World Wide Web Conference in Perth, Australia. This is the most comprehensive investigation of sock puppets in discussion forums, says Meng Jiang, who studies suspicious online behaviour at the University of Illinois at Urbana-Champaign. But given that the group used sock puppets already identified by their IPs, it’s impossible to know if the tool could detect sock puppets the IP approach missed, he says. A real-world system would likely incorporate both approaches. Kumar is confident the new tool could detect other sock puppets, and points out that IP addresses are not always available and can easily be spoofed. The system could be useful to detect sock puppets on any forum that makes an account’s posting history available, such as social media site Reddit and most websites’ comment sections, he says. A person could then verify if an account breaches the site’s rules. “These tools always have a human in the loop,” he says. “It would flag suspicious accounts and a moderator would decide.”


News Article | April 21, 2017
Site: www.rdmag.com

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics. "The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including biological and structural health monitoring sensors," explained Sameh Tawfick, an assistant professor of mechanical science and engineering at Illinois. "Aligned carbon nanotube sheets are suitable for a wide range of application spanning the micro- to the macro-scales including Micro-Electro-Mechanical Systems (MEMS), supercapacitor electrodes, electrical cables, artificial muscles, and multi-functional composites. "To our knowledge, this is the first study to apply the principles of fracture mechanics to design and study the toughness nano-architectured CNT textiles. The theoretical framework of fracture mechanics is shown to be very robust for a variety of linear and non-linear materials." Carbon nanotubes, which have been around since the early nineties, have been hailed as a "wonder material" for numerous nanotechnology applications, and rightly so. These tiny cylindrical structures made from wrapped graphene sheets have diameter of a few nanometers--about 1000 times thinner than a human hair, yet, a single carbon nanotube is stronger than steel and carbon fibers, more conductive than copper, and lighter than aluminum. However, it has proven really difficult to construct materials, such as fabrics or films that demonstrate these properties on centimeter or meter scales. The challenge stems from the difficulty of assembling and weaving CNTs since they are so small, and their geometry is very hard to control. "The study of the fracture energy of CNT textiles led us to design these extremely tough films," stated Yue Liang, a former graduate student with the Kinetic Materials Research group and lead author of the paper, "Tough Nano-Architectured Conductive Textile Made by Capillary Splicing of Carbon Nanotubes," appearing in Advanced Engineering Materials. To our knowledge, this is the first study of the fracture energy of CNT textiles. Beginning with catalyst deposited on a silicon oxide substrate, vertically aligned carbon nanotubes were synthesized via chemical vapor deposition in the form of parallel lines of 5?μm width, 10?μm length, and 20-60?μm heights. "The staggered catalyst pattern is inspired by the brick and mortar design motif commonly seen in tough natural materials such as bone, nacre, the glass sea sponge, and bamboo," Liang added. "Looking for ways to staple the CNTs together, we were inspired by the splicing process developed by ancient Egyptians 5,000 years ago to make linen textiles. We tried several mechanical approaches including micro-rolling and simple mechanical compression to simultaneously re-orient the nanotubes, then, finally, we used the self-driven capillary forces to staple the CNTs together." "This work combines careful synthesis, and delicate experimentation and modeling," Tawfick said. "Flexible electronics are subject to repeated bending and stretching, which could cause their mechanical failure. This new CNT textile, with simple flexible encapsulation in an elastomer matrix, can be used in smart textiles, smart skins, and a variety of flexible electronics. Owing to their extremely high toughness, they represent an attractive material, which can replace thin metal films to enhance device reliability."


Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles, that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics. “The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including biological and structural health monitoring sensors,” explained Sameh Tawfick, an assistant professor of mechanical science and engineering at Illinois. “Aligned carbon nanotube sheets are suitable for a wide range of application spanning the micro- to the macro-scales including Micro-Electro-Mechanical Systems (MEMS), supercapacitor electrodes, electrical cables, artificial muscles, and multi-functional composites. “To our knowledge, this is the first study to apply the principles of fracture mechanics to design and study the toughness nano-architectured CNT textiles. The theoretical framework of fracture mechanics is shown to be very robust for a variety of linear and non-linear materials.” Carbon nanotubes, which have been around since the early nineties, have been hailed as a “wonder material” for numerous nanotechnology applications, and rightly so. These tiny cylindrical structures made from wrapped graphene sheets have diameter of a few nanometers—about 1000 times thinner than a human hair, yet, a single carbon nanotube is stronger than steel and carbon fibers, more conductive than copper, and lighter than aluminum. However, it has proven really difficult to construct materials, such as fabrics or films that demonstrate these properties on centimeter or meter scales. The challenge stems from the difficulty of assembling and weaving CNTs since they are so small, and their geometry is very hard to control. “The study of the fracture energy of CNT textiles led us to design these extremely tough films,” stated Yue Liang, a former graduate student with the Kinetic Materials Research group and lead author of the paper, “Tough Nano-Architectured Conductive Textile Made by Capillary Splicing of Carbon Nanotubes,” appearing in Advanced Engineering Materials. To our knowledge, this is the first study of the fracture energy of CNT textiles. Beginning with catalyst deposited on a silicon oxide substrate, vertically aligned carbon nanotubes were synthesized via chemical vapor deposition in the form of parallel lines of 5 µm width, 10 μm length, and 20–60 μm heights. “The staggered catalyst pattern is inspired by the brick and mortar design motif commonly seen in tough natural materials such as bone, nacre, the glass sea sponge, and bamboo,” Liang added. “Looking for ways to staple the CNTs together, we were inspired by the splicing process developed by ancient Egyptians 5,000 years ago to make linen textiles. We tried several mechanical approaches including micro-rolling and simple mechanical compression to simultaneously re-orient the nanotubes, then, finally, we used the self-driven capillary forces to staple the CNTs together.” “This work combines careful synthesis, and delicate experimentation and modeling,” Tawfick said. “Flexible electronics are subject to repeated bending and stretching, which could cause their mechanical failure. This new CNT textile, with simple flexible encapsulation in an elastomer matrix, can be used in smart textiles, smart skins, and a variety of flexible electronics. Owing to their extremely high toughness, they represent an attractive material, which can replace thin metal films to enhance device reliability.” In addition to Liang and Tawfick, co-authors include David Sias and Ping Ju Chen.


Using an atomic quantum simulator, scientists at the University of Illinois at Urbana-Champaign have achieved the first-ever direct observation of chiral currents in the model topological insulator, the 2-D integer quantum Hall system.


News Article | April 29, 2017
Site: www.prweb.com

LearnHowToBecome.org, a leading resource provider for higher education and career information, has determined which online colleges and universities in the U.S. have the most military-friendly programs and services. Of the 50 four-year schools that earned honors, Drexel University, University of Southern California, Duquesne University, Regis University and Harvard University were the top five. 50 two-year schools were also recognized; Laramie County Community College, Western Wyoming Community College, Dakota College at Bottineau, Mesa Community College and Kansas City Kansas Community College ranked as the top five. A complete list of top schools is included below. “Veterans and active duty members of the military often face unique challenges when it comes to transitioning into college, from navigating the GI Bill to getting used to civilian life,” said Wes Ricketts, senior vice president of LearnHowToBecome.org. “These online schools not only offer military-friendly resources, they also offer an online format, allowing even the busiest members of our armed forces to earn a degree or certificate.” To be included on the “Most Military-Friendly Online Colleges” list, schools must be regionally accredited, not-for-profit institutions. Each college is also evaluated on additional data points such as the number and variety of degree programs offered, military tuition rates, employment services, post-college earnings of alumni and military-related academic resources. Complete details on each college, their individual scores and the data and methodology used to determine the LearnHowToBecome.org “Most Military-Friendly Online Colleges” list, visit: The Most Military-Friendly Online Four-Year Colleges in the U.S. for 2017 include: Arizona State University-Tempe Auburn University Azusa Pacific University Baker University Boston University Canisius College Carnegie Mellon University Columbia University in the City of New York Creighton University Dallas Baptist University Drexel University Duquesne University George Mason University Hampton University Harvard University Illinois Institute of Technology Iowa State University La Salle University Lawrence Technological University Lewis University Loyola University Chicago Miami University-Oxford Michigan Technological University Missouri University of Science and Technology North Carolina State University at Raleigh Norwich University Oklahoma State University-Main Campus Pennsylvania State University-Main Campus Purdue University-Main Campus Regis University Rochester Institute of Technology Saint Leo University Southern Methodist University Syracuse University Texas A & M University-College Station University of Arizona University of Denver University of Florida University of Idaho University of Illinois at Urbana-Champaign University of Michigan-Ann Arbor University of Minnesota-Twin Cities University of Mississippi University of Missouri-Columbia University of North Carolina at Chapel Hill University of Oklahoma-Norman Campus University of Southern California University of the Incarnate Word Washington State University Webster University The Most Military-Friendly Online Two-Year Colleges in the U.S. for 2017 include: Aims Community College Allen County Community College Amarillo College Barton County Community College Bunker Hill Community College Casper College Central Texas College Chandler-Gilbert Community College Cincinnati State Technical and Community College Cochise College Columbus State Community College Cowley County Community College Craven Community College Dakota College at Bottineau East Mississippi Community College Eastern New Mexico University - Roswell Campus Edmonds Community College Fox Valley Technical College GateWay Community College Grayson College Hutchinson Community College Kansas City Kansas Community College Lake Region State College Laramie County Community College Lone Star College Mesa Community College Metropolitan Community College Mitchell Technical Institute Mount Wachusett Community College Navarro College Northeast Community College Norwalk Community College Ozarka College Phoenix College Prince George's Community College Quinsigamond Community College Rio Salado College Rose State College Sheridan College Shoreline Community College Sinclair College Southeast Community College Southwestern Oregon Community College State Fair Community College Truckee Meadows Community College Western Nebraska Community College Western Oklahoma State College Western Texas College Western Wyoming Community College Yavapai College ### About Us: LearnHowtoBecome.org was founded in 2013 to provide data and expert driven information about employment opportunities and the education needed to land the perfect career. Our materials cover a wide range of professions, industries and degree programs, and are designed for people who want to choose, change or advance their careers. We also provide helpful resources and guides that address social issues, financial aid and other special interest in higher education. Information from LearnHowtoBecome.org has proudly been featured by more than 700 educational institutions.


News Article | May 5, 2017
Site: www.prweb.com

LearnHowToBecome.org, a leading resource provider for higher education and career information, has released its list of the Best Colleges in Illinois for 2017. 50 four-year colleges were ranked, with Northwestern University, University of Chicago, Bradley University, Illinois Institute of Technology and Augustana College taking the top five spots on the list. 49 two-year schools were also selected; Carl Sandburg College, Illinois Central College, Richland Community College, Rend Lake College and Lincoln Land Community College were the top five. A complete list of schools is included below. “The schools on our list have shown that they offer outstanding educational programs that set students up for post-college success,” said Wes Ricketts, senior vice president of LearnHowToBecome.org. “Students exploring higher education options in Illinois can also look to these schools to provide top-quality resources that help maximize the overall educational experience.” To be included on the “Best Colleges in Illinois” list, all schools must be not-for-profit and regionally accredited. Each college is also evaluated metrics including annual alumni earnings, the opportunity for employment services and academic counseling, the selection of degree programs offered, financial aid availability and graduation rates. Complete details on each college, their individual scores and the data and methodology used to determine the LearnHowToBecome.org “Best Colleges in Illinois” list, visit: The Best Four-Year Colleges in Illinois for 2017 include: Augustana College Aurora University Benedictine University Blackburn College Bradley University Chicago State University Concordia University-Chicago DePaul University Dominican University Eastern Illinois University Elmhurst College Eureka College Governors State University Greenville College Illinois College Illinois Institute of Technology Illinois State University Illinois Wesleyan University Judson University Knox College Lake Forest College Lewis University Loyola University Chicago MacMurray College McKendree University Millikin University Monmouth College National Louis University North Central College North Park University Northern Illinois University Northwestern University Olivet Nazarene University Principia College Quincy University Rockford University Roosevelt University Rush University Saint Xavier University Southern Illinois University-Carbondale Southern Illinois University-Edwardsville Trinity Christian College Trinity International University-Illinois University of Chicago University of Illinois at Chicago University of Illinois at Springfield University of Illinois at Urbana-Champaign University of St Francis Western Illinois University Wheaton College The Best Two-Year Colleges in Illinois for 2017 include: Black Hawk College Carl Sandburg College City Colleges of Chicago - Harry S Truman College City Colleges of Chicago - Malcolm X College City Colleges of Chicago - Wilbur Wright College City Colleges of Chicago-Harold Washington College City Colleges of Chicago-Kennedy-King College City Colleges of Chicago-Olive-Harvey College City Colleges of Chicago-Richard J Daley College College of DuPage College of Lake County Danville Area Community College Elgin Community College Frontier Community College Harper College Heartland Community College Highland Community College Illinois Central College Illinois Valley Community College John A Logan College John Wood Community College Joliet Junior College Kankakee Community College Kaskaskia College Kishwaukee College Lake Land College Lewis and Clark Community College Lincoln Land Community College Lincoln Trail College MacCormac College McHenry County College Moraine Valley Community College Morton College Oakton Community College Olney Central College Parkland College Prairie State College Rend Lake College Richland Community College Rock Valley College Sauk Valley Community College Shawnee Community College South Suburban College Southeastern Illinois College Southwestern Illinois College Spoon River College Triton College Wabash Valley College Waubonsee Community College ### About Us: LearnHowtoBecome.org was founded in 2013 to provide data and expert driven information about employment opportunities and the education needed to land the perfect career. Our materials cover a wide range of professions, industries and degree programs, and are designed for people who want to choose, change or advance their careers. We also provide helpful resources and guides that address social issues, financial aid and other special interest in higher education. Information from LearnHowtoBecome.org has proudly been featured by more than 700 educational institutions.


News Article | May 4, 2017
Site: www.eurekalert.org

If we believe that we can personally help stop climate change with individual actions -- such as turning the thermostat down -- then we are more likely to make a difference, according to research from the University of Warwick If we believe that we can personally help stop climate change with individual actions - such as turning the thermostat down -- then we are more likely to make a difference, according to research from the University of Warwick. Dr Jesse Preston in the Department of Psychology has demonstrated that people are often negatively affected by climate change helplessness -- the belief that climate change is so massive and terrifying, as to be out of our personal control, and that our actions are too small to help. This feeling of helplessness, however, makes people less likely to bother with individual eco-friendly actions - and actually leads to higher energy consumption. In one study, the researchers tested a group of over two hundred people, and gave different members of the group varying messages about climate change. Some were given a High Efficacy Climate Change message (that personal actions do make a difference in the fight against climate change); others a Helpless Climate Change message (that personal actions make no difference); and some were given no message at all. Over the next week, the group reported whether or not they adopted behaviours to help stop climate change - such as driving less, hanging washing on the line instead of using the dryer, using less water, or turning the heating down. The people who had received the High Efficacy Climate Change message reported 16.5% more of these behaviours than those who read a Helpless Climate Change message - and 13% more actions than the control group which received no message. Moreover, people in the group which was told their actions couldn't make a difference to climate change actually reported higher energy usage than before -- showing how destructive a feeling of helplessness can be. The researchers also found that a belief that personal behaviours make a difference enhances the moralisation of our actions - the notion that they are 'good' or 'bad' -- and an awareness that the energy we individually consume could either prevent or cause damage to human life. Public messages about climate change which focus on how we can help make a difference as individuals will be far more effective in encouraging people to consume less energy, according to the researchers. "Often climate change messages try to persuade the public by increasing belief that climate change is real, or through fear of its dire consequences. But mere belief in climate change is not enough, and fear can backfire if we feel helpless and overwhelmed. "It is vitally important that individuals appreciate the impact and value of their own actions for us to make a meaningful change as a whole." The paper, 'Climate Change Helplessness and the (De)moralization of Individual Energy Behavior', is published in Journal of Experimental Psychology: Applied. It is co-authored by Erika Salomon and Melanie B. Tannenbaum from the University of Illinois at Urbana-Champaign, USA.


LIVERMORE, Calif. - Researchers at Sandia National Laboratories have developed new mathematical techniques to advance the study of molecules at the quantum level. Mathematical and algorithmic developments along these lines are necessary for enabling the detailed study of complex hydrocarbon molecules that are relevant in engine combustion. Existing methods to approximate potential energy functions at the quantum scale need too much computer power and are thus limited to small molecules. Sandia researchers say their technique will speed up quantum mechanical computations and improve predictions made by theoretical chemistry models. Given the computational speedup, these methods can potentially be applied to bigger molecules. Sandia postdoctoral researcher Prashant Rai worked with researchers Khachik Sargsyan and Habib Najm at Sandia's Combustion Research Facility and collaborated with quantum chemists So Hirata and Matthew Hermes at the University of Illinois at Urbana-Champaign. Computing energy at fewer geometric arrangements than normally required, the team developed computationally efficient methods to approximate potential energy surfaces. A precise understanding of potential energy surfaces, key elements in virtually all calculations of quantum dynamics, is required to accurately estimate the energy and frequency of vibrational modes of molecules. "If we can find the energy of the molecule for all possible configurations, we can determine important information, such as stable states of molecular transition structure or intermediate states of molecules in chemical reactions," Rai said. Initial results of this research were published in Molecular Physics in an article titled "Low-rank canonical-tensor decomposition of potential energy surfaces: application to grid-based diagrammatic vibrational Green's function theory." "Approximating potential energy surfaces of bigger molecules is an extremely challenging task due to the exponential increase in information required to describe them with each additional atom in the system," Rai said. "In mathematics, it is termed the Curse of Dimensionality." The key to beating the curse of dimensionality is to exploit the characteristics of the specific structure of the potential energy surfaces. Rai said this structure information can then be used to approximate the requisite high dimensional functions. "We make use of the fact that although potential energy surfaces can be high dimensional, they can be well approximated as a small sum of products of one-dimensional functions. This is known as the low-rank structure, where the rank of the potential energy surface is the number of terms in the sum," Rai said. "Such an assumption on structure is quite general and has also been used in similar problems in other fields. Mathematically, the intuition of low-rank approximation techniques comes from multilinear algebra where the function is interpreted as a tensor and is decomposed using standard tensor decomposition techniques." The energy and frequency corrections are formulated as integrals of these high-dimensional energy functions. Approximation in such a low-rank format renders these functions easily integrable as it breaks the integration problem to the sum of products of one- or two-dimensional integrals, so standard integration methods apply. The team tried out their computational methods on small molecules such as water and formaldehyde. Compared to the classical Monte Carlo method, the randomness-based standard workhorse for high dimensional integration problems, their approach predicted energy and frequency of water molecule that were more accurate, and it was at least 1,000 times more computationally efficient. Rai said the next step is to further enhance the technique by challenging it with bigger molecules, such as benzene. "Interdisciplinary studies, such as quantum chemistry and combustion engineering, provide opportunities for cross pollination of ideas, thereby providing a new perspective on problems and their possible solutions," Rai said. "It is also a step towards using recent advances in data science as a pillar of scientific discovery in future." Sandia National Laboratories is a multimission laboratory operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy's National Nuclear Security Administration. Sandia has major research and development responsibilities in nuclear deterrence, global security, defense, energy technologies and economic competitiveness, with main facilities in Albuquerque, New Mexico, and Livermore, California.


News Article | May 3, 2017
Site: www.eurekalert.org

VIDEO:  Extension of Continental, Marginal and Marine environments from ~18.4 to ~10.5 Ma showing the the two marine incursions reported in this study. view more A tiny shark tooth, part of a mantis shrimp and other microscopic marine organisms reveal that as the Andes rose, the Eastern Amazon sank twice, each time for less than a million years. Water from the Caribbean flooded the region from Venezuela to northwestern Brazil. These new findings by Smithsonian scientists and colleagues, published this week in Science Advances, fuel an ongoing controversy regarding the geologic history of the region. "Pollen records from oil wells in eastern Colombia and outcrops in northwestern Brazil clearly show two short-lived events in which ocean water from the Caribbean flooded what is now the northwest part of the Amazon basin," said Carlos Jaramillo, staff scientist at the Smithsonian Tropical Research Institute and lead author of the study. "Geologists disagree about the origins of the sediments in this area, but we provide clear evidence that they are of marine origin, and that the flooding events were fairly brief," Jaramillo said. His team dated the two flooding events to between 17 to18 million years ago and between 16 to 12 million years ago. Several controversial interpretations of the history of the region include the existence of a large, shallow sea covering the Amazon for millions of years, a freshwater megalake, shifting lowland rivers occasionally flooded by seawater, frequent seawater incusions, and a long-lived "para-marine metalake," which has no modern analog. Jaramillo assembled a diverse team from the Smithsonian and the University of Illinois at Urbana-Champaign; Corporacion Geologica Ares; the University of Birmingham; the University of Ghent; the Universidad del Norte, Baranquilla, Colombia; the University of Alberta, Edmonton; the University of Zurich; Ecopetrol, S.A.; Hocol, S.A.; the Royal Netherlands Institute for Sea Research at Utrecht University; the University of Texas of the Permian Basin; and the Naturalis Biodiversity Center. Together, they examined evidence including more than 50,000 individual pollen grains representing more than 900 pollen types from oil drilling cores from the Saltarin region of Colombia and found two distinct layers of marine pollen separated by layers of non-marine pollen types. They also found several fossils of marine organisms in the lower layer: a shark tooth and a mantis shrimp. "It's important to understand changes across the vast Amazonian landscape that had a profound effect, both on the evolution and distribution of life there and on the modern and ancient climates of the continent," Jaramillo said. The Smithsonian Tropical Research Institute, headquartered in Panama City, Panama, is a part of the Smithsonian Institution. The Institute furthers the understanding of tropical nature and its importance to human welfare, trains students to conduct research in the tropics and promotes conservation by increasing public awareness of the beauty and importance of tropical ecosystems. STRI website: http://www. . C. Jaramillo, I. Romero, C. D'Apolito, J. Ortiz. "Miocene flooding events of western Amazonia." Science Advances. Manuscript Number: sciadv.1601693; Smithsonian Tropical Research Institute


Patent
University of Illinois at Urbana - Champaign | Date: 2017-03-22

Biomimetic grafts or implants coated with an osteogenic extracellular matrix and methods for production and use are described.


Patent
University of Illinois at Urbana - Champaign | Date: 2017-03-22

Disclosed is a derivative of amphotericin B (AmB), denoted C2epiAmB, with an improved therapeutic index over amphotericin B, pharmaceutical compositions comprising the AmB derivative, methods of making the AmB derivative and the pharmaceutical composition, and their use in methods of inhibiting growth of a yeast or fungus and treating a yeast or fungal infection. C2epiAmB is an epimer of the parent compound. Specifically, C2epiAmB differs from the parent compound at the C2 stereogenic center on mycosamine. This difference in structure results in (i) retained capacity to bind ergosterol and inhibit growth of yeast, (ii) greatly reduced capacity to bind cholesterol, and (iii) essentially no toxicity to human cells.


News Article | May 6, 2017
Site: www.greencarcongress.com

« Saft team develops first metal hydride - sulfur Li-ion battery | Main | New molybdenum-coated catalyst produces hydrogen from water-splitting more efficiently; preventing the back reaction » In a new open-access paper in Nature Communications, University of Illinois at Urbana-Champaign researchers describe how their successful integration of several cutting-edge technologies—creation of standardized genetic components, implementation of customizable genome editing tools, and large-scale automation of molecular biology laboratory tasks—will enhance the ability to work with yeast. The results of their new method demonstrate its potential to produce valuable novel strains of yeast for industrial use, as well as to reveal a more sophisticated understanding of the yeast genome. The team focused on yeast in part because of its important modern-day applications; yeasts are used to convert the sugars of biomass feedstocks into biofuels such as ethanol and industrial chemicals such as lactic acid, or to break down organic pollutants. Because yeast and other fungi, like humans, are eukaryotes, organisms with a compartmentalized cellular structure and complex mechanisms for control of their gene activity, study of yeast genome function is also a key component of biomedical research. The goal of the work was really to develop a genome-scale engineering tool for yeast … traditional metabolic engineering focused on just a few genes and the few existing genome-scale engineering tools are only applicable to bacteria, not eukaryotic organisms like yeast. A second innovation is the use of synthetic biology concepts, the modularization of the parts, and integration with a robotic system, so we can do it in high-throughput. —Study leader Huimin Zhao, the Steven L. Miller Chair of Chemical and Biomolecular Engineering The group took the first step toward their goal of a novel engineering strategy for yeast by creating what is known as a cDNA library: a collection of more than 90% of the genes from the genome of baker’s yeast (Saccharomyces cerevisiae), arranged within a custom segment of DNA so that each gene will be, in one version, overactive within a yeast cell, and in a second version, reduced in activity. Zhao and colleagues examined the ability of the CRISPR-Cas system, a set of molecules borrowed from a form of immune system in bacteria (CRISPR stands for clustered regularly interspaced short palindromic repeats, describing a feature of this system in bacterial genomes). This system allowed Zhao to make precise cuts in the yeast genome, into which the standardized genetic parts from their library could insert themselves. With gene activity-modulating parts integrating into the genome with such high efficiency, the researchers were able randomly to generate many different strains of yeast, each with its own unique set of modifications. These strains were subjected to artificial selection processes to identify those that had desirable traits, such as the ability to survive exposure to reagents used in the biofuel production process. This selection process was greatly aided by the Illinois Biological Foundry for Advanced Biomanufacturing (iBioFAB), a robotic system that performs most of the laboratory work described above in an automated way, including selection of promising yeast strains. Use of iBioFAB greatly accelerated the work, enabling simultaneous creation and testing of many unique strains. The iBioFAB was conceived and developed by the Biosystems Design research theme at the Carl R. Woese Institute for Genomic Biology (IGB), which is led by Zhao. With support from the High Performance Biological Computing Group at Illinois, Zhao, Si and their colleagues analyzed the modified genomes of their most promising yeast strains. They identified combinations of genes whose altered activities contributed to desirable traits; the functions of some of these genes were previously unknown, demonstrating the technique’s ability to generate new biological knowledge. I think the key difference between this method and the other existing metabolic engineering strategies in yeast is really the scale. The current metabolic engineering strategies are all focused on just a few genes, dozens of genes at most … it’s very intuitive. With this we can explore all the genes, we can identify a lot of targets that cannot be intuited. The work, which was funded by the Roy J. Carver Charitable Trust, IGB, Defense Advanced Research Program Agency (DARPA), and National Academies Keck Futures Initiative on Synthetic Biology, paves the way for similar approaches to broad-scale, automated genome engineering of other eukaryotic species.


Abstract: Researchers at Sandia National Laboratories have developed new mathematical techniques to advance the study of molecules at the quantum level. Mathematical and algorithmic developments along these lines are necessary for enabling the detailed study of complex hydrocarbon molecules that are relevant in engine combustion. Existing methods to approximate potential energy functions at the quantum scale need too much computer power and are thus limited to small molecules. Sandia researchers say their technique will speed up quantum mechanical computations and improve predictions made by theoretical chemistry models. Given the computational speedup, these methods can potentially be applied to bigger molecules. Sandia postdoctoral researcher Prashant Rai worked with researchers Khachik Sargsyan and Habib Najm at Sandia's Combustion Research Facility and collaborated with quantum chemists So Hirata and Matthew Hermes at the University of Illinois at Urbana-Champaign. Computing energy at fewer geometric arrangements than normally required, the team developed computationally efficient methods to approximate potential energy surfaces. A precise understanding of potential energy surfaces, key elements in virtually all calculations of quantum dynamics, is required to accurately estimate the energy and frequency of vibrational modes of molecules. "If we can find the energy of the molecule for all possible configurations, we can determine important information, such as stable states of molecular transition structure or intermediate states of molecules in chemical reactions," Rai said. Initial results of this research were published in Molecular Physics in an article titled "Low-rank canonical-tensor decomposition of potential energy surfaces: application to grid-based diagrammatic vibrational Green's function theory." "Approximating potential energy surfaces of bigger molecules is an extremely challenging task due to the exponential increase in information required to describe them with each additional atom in the system," Rai said. "In mathematics, it is termed the Curse of Dimensionality." Beating the curse The key to beating the curse of dimensionality is to exploit the characteristics of the specific structure of the potential energy surfaces. Rai said this structure information can then be used to approximate the requisite high dimensional functions. "We make use of the fact that although potential energy surfaces can be high dimensional, they can be well approximated as a small sum of products of one-dimensional functions. This is known as the low-rank structure, where the rank of the potential energy surface is the number of terms in the sum," Rai said. "Such an assumption on structure is quite general and has also been used in similar problems in other fields. Mathematically, the intuition of low-rank approximation techniques comes from multilinear algebra where the function is interpreted as a tensor and is decomposed using standard tensor decomposition techniques." The energy and frequency corrections are formulated as integrals of these high-dimensional energy functions. Approximation in such a low-rank format renders these functions easily integrable as it breaks the integration problem to the sum of products of one- or two-dimensional integrals, so standard integration methods apply. The team tried out their computational methods on small molecules such as water and formaldehyde. Compared to the classical Monte Carlo method, the randomness-based standard workhorse for high dimensional integration problems, their approach predicted energy and frequency of water molecule that were more accurate, and it was at least 1,000 times more computationally efficient. Rai said the next step is to further enhance the technique by challenging it with bigger molecules, such as benzene. "Interdisciplinary studies, such as quantum chemistry and combustion engineering, provide opportunities for cross pollination of ideas, thereby providing a new perspective on problems and their possible solutions," Rai said. "It is also a step towards using recent advances in data science as a pillar of scientific discovery in future." About Sandia National Labratories Sandia National Laboratories is a multimission laboratory operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy's National Nuclear Security Administration. Sandia has major research and development responsibilities in nuclear deterrence, global security, defense, energy technologies and economic competitiveness, with main facilities in Albuquerque, New Mexico, and Livermore, California. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


Researchers at Sandia National Laboratories have developed new mathematical techniques to advance the study of molecules at the quantum level. Mathematical and algorithmic developments along these lines are necessary for enabling the detailed study of complex hydrocarbon molecules that are relevant in engine combustion. Existing methods to approximate potential energy functions at the quantum scale need too much computer power and are thus limited to small molecules. Sandia researchers say their technique will speed up quantum mechanical computations and improve predictions made by theoretical chemistry models. Given the computational speedup, these methods can potentially be applied to bigger molecules. Sandia postdoctoral researcher Prashant Rai worked with researchers Khachik Sargsyan and Habib Najm at Sandia's Combustion Research Facility and collaborated with quantum chemists So Hirata and Matthew Hermes at the University of Illinois at Urbana-Champaign. Computing energy at fewer geometric arrangements than normally required, the team developed computationally efficient methods to approximate potential energy surfaces. A precise understanding of potential energy surfaces, key elements in virtually all calculations of quantum dynamics, is required to accurately estimate the energy and frequency of vibrational modes of molecules. "If we can find the energy of the molecule for all possible configurations, we can determine important information, such as stable states of molecular transition structure or intermediate states of molecules in chemical reactions," Rai said. Initial results of this research were published in Molecular Physics in an article titled "Low-rank canonical-tensor decomposition of potential energy surfaces: application to grid-based diagrammatic vibrational Green's function theory." "Approximating potential energy surfaces of bigger molecules is an extremely challenging task due to the exponential increase in information required to describe them with each additional atom in the system," Rai said. "In mathematics, it is termed the Curse of Dimensionality." The key to beating the curse of dimensionality is to exploit the characteristics of the specific structure of the potential energy surfaces. Rai said this structure information can then be used to approximate the requisite high dimensional functions. "We make use of the fact that although potential energy surfaces can be high dimensional, they can be well approximated as a small sum of products of one-dimensional functions. This is known as the low-rank structure, where the rank of the potential energy surface is the number of terms in the sum," Rai said. "Such an assumption on structure is quite general and has also been used in similar problems in other fields. Mathematically, the intuition of low-rank approximation techniques comes from multilinear algebra where the function is interpreted as a tensor and is decomposed using standard tensor decomposition techniques." The energy and frequency corrections are formulated as integrals of these high-dimensional energy functions. Approximation in such a low-rank format renders these functions easily integrable as it breaks the integration problem to the sum of products of one- or two-dimensional integrals, so standard integration methods apply. The team tried out their computational methods on small molecules such as water and formaldehyde. Compared to the classical Monte Carlo method, the randomness-based standard workhorse for high dimensional integration problems, their approach predicted energy and frequency of water molecule that were more accurate, and it was at least 1,000 times more computationally efficient. Rai said the next step is to further enhance the technique by challenging it with bigger molecules, such as benzene. "Interdisciplinary studies, such as quantum chemistry and combustion engineering, provide opportunities for cross pollination of ideas, thereby providing a new perspective on problems and their possible solutions," Rai said. "It is also a step towards using recent advances in data science as a pillar of scientific discovery in future."


News Article | May 8, 2017
Site: www.prweb.com

The DuPage County law firm of Momkus McCluskey Roberts LLC is proud to welcome Attorney Kristy K. Singler to its staff. As an Associate Attorney focusing on legal services in insurance litigation and coverage, healthcare law, and commercial and civil litigation, Mrs. Singler offers dedication and compassion when serving clients throughout the Northern Illinois area. Attorney Kristy K. Singler attended Loyola University Chicago School of Law where she received her J.D., and she earned her undergraduate degree in Political Science from the University of Illinois at Urbana-Champaign. Mrs. Singler was admitted to the Illinois State Bar in 1999. DuPage County lawyer Kristy K. Singler has received honorable accolades such as numerous “Rising Star” nominations from Chicago Magazine. She earned this accolade for four consecutive years, from 2008 to 2011. Mrs. Singler was a member of the Chicago Inns of Court and maintains active memberships with local and state bar associations. Mrs. Singler was previously a partner at a Hinshaw Culbertson LLC. In response to Mrs. Singler’s new position at the firm, Managing Partner Jennifer L. Friedland stated, “We welcome Attorney Kristy Singler to our practice, and we know she will bring continued to success to the firm. We are happy to have her as a new Associate.” As one of the largest full-service law firms in the Chicago area, Momkus McCluskey Roberts LLC serves individuals and large and small businesses in many diverse areas of practice. The experienced attorneys at the firm provide legal representation for matters involving commercial and civil litigation, business law, healthcare law, banking and finance, insurance litigation and coverage, family law, commercial real estate, estate planning, and appeals. Call the Momkus McCluskey Roberts LLC main office at 630-434-0400 to schedule an initial consultation.


News Article | April 17, 2017
Site: www.eurekalert.org

HOUSTON -- (April 12, 2017) -- Rice University professor and engineer Richard Baraniuk has been elected to the American Academy of Arts and Sciences. He is one of 228 new members announced today by the academy, which honors some of the world's most accomplished scholars, scientists, writers, artists and civic, business and philanthropic leaders. Baraniuk is the Victor E. Cameron Professor of Electrical and Computer Engineering at Rice. Others in the academy's Class of 2017 include philanthropist and singer-songwriter John Legend, actress Carol Burnett, chairman of the board of Xerox Corp. Ursula Burns, mathematician Maryam Mirzakhani, immunologist James P. Allison, writer Chimamanda Ngozi Adichie and Pulitzer Prize winners, MacArthur Fellows and winners of the Academy, Grammy, Emmy and Tony awards. "In a tradition reaching back to the earliest days of our nation, the honor of election to the American Academy is also a call to service," said Academy President Jonathan F. Fanton. "Through our projects, publications and events, the academy provides members with opportunities to make common cause and produce the useful knowledge for which the academy's 1780 charter calls." Baraniuk is one of the world's leading experts on machine learning and compressive sensing, a branch of signal processing that enables engineers to deduce useful information from far fewer data samples than would ordinarily be required. He is a co-inventor of the single-pixel camera and of the FlatCam, a lens-less camera that is thinner than a dime and can be fabricated like a microchip. A pioneer in education, Baraniuk founded Rice-based Connexions in 1999 to bring textbooks and other learning materials to the internet. Next came OpenStax, which provides high-quality, peer-reviewed, college-level textbooks to students worldwide as free downloads or low-cost printed publications. More than 1.8 million college students have used one of the 27 textbooks published by OpenStax. These textbooks are estimated to have saved students more than $100 million during the 2016-17 academic year. Baraniuk is also using OpenStax to develop a software platform for textbooks that deliver personalized lessons. The American Academy of Arts and Sciences membership comes less than a month after Baraniuk was selected as one of 13 Vannevar Bush Faculty Fellows -- one of the Defense Department's most coveted basic research awards for U.S. university scientists and engineers -- and a week after he was inducted into the National Academy of Inventors as a fellow. "It was a complete, total surprise," Baraniuk said about the announcement that the academy had elected him. "It's fantastic news. And it's a tribute to all the tremendous mentors I've had at Rice and my colleagues around the globe. This would never have happened without their guidance and support." Baraniuk was raised in Winnipeg, Canada. He has three degrees in electrical and computer engineering: a B.S. from the University of Manitoba, an M.S. from the University of Wisconsin and a Ph.D. from the University of Illinois at Urbana-Champaign. He holds 28 U.S. patents and six foreign patents in signal processing and acquisition. He came to Rice in 1992 and has received multiple teaching awards as a member of the faculty. Baraniuk is also a fellow of the American Association for the Advancement of Science and of the Institute of Electrical and Electronic Engineers (IEEE). Three times he has been named a Thomson Reuters Highly Cited Researcher. Among his other honors and awards are the 2012 Compressive Sampling Pioneer Award and the 2008 Wavelet Pioneer Award, both from the International Society for Optics and Photonics, and the IEEE Signal Processing Society's Best Paper (2015), Technical Achievement (2014) and Education (2010) awards. The American Academy of Arts and Sciences' new honorees will be inducted at a ceremony Oct. 7 in Cambridge, Mass. The list of the 237th class of new members is available at http://www. . The academy is one of the country's oldest learned societies and independent policy research centers. It convenes leaders from the academic, business and government sectors to respond to the challenges facing -- and opportunities available to -- the nation and the world. Members contribute to academy publications and studies in science, engineering and technology policy; global security and international affairs; the humanities, arts and education; and American institutions and the public good.


News Article | April 21, 2017
Site: www.materialstoday.com

In a surprising new discovery, alpha-tin, commonly called gray tin, exhibits a novel electronic phase when its crystal structure is strained, putting it in a rare new class of three-dimensional (3D) materials called topological Dirac semi-metals (TDSs). Only two other TDS materials are known to exist, discovered as recently as 2013. Alpha-tin now joins this class as its only simple-element member. This discovery, which is reported in a paper in Physical Review Letters, holds promise for novel physics and many potential technological applications. It is the work of Caizhi Xu, a physics graduate student at the University of Illinois at Urbana-Champaign, working under Tai-Chang Chiang and in collaboration with scientists at the Advanced Light Source at the Lawrence Berkeley National Laboratory and six other institutions internationally. TDSs exhibit electronic properties akin to those found at the surface of the now much-studied topological insulators (TIs). At the surfaces of TIs, electrons are able to conduct freely, like in a metal, while the ‘bulk’ or interior acts as an insulator. The surface electrons behave as two-dimensional (2D) massless, spin-polarized Dirac fermions that are robust against non-magnetic impurities, giving them potential applications in spintronic devices and fault-tolerant quantum computing. By contrast, the bulk electrons in TDSs can behave as massless Dirac fermions in all three dimensions, which leads to additional possibilities for novel physical behaviors. "TDSs are of profound interest to condensed matter physicists, primarily because they exhibit a number of novel physical properties, including ultrahigh carrier mobility, giant linear magnetoresistance, chiral anomaly and novel quantum oscillations," explains Xu. "Secondly, this class of materials can realize many interesting topological phases – under controlled conditions, the material can undergo phase transitions and can become a topological insulator, a Weyl semimetal or a topological superconductor." Tin has two well-known allotropes: at 13.2°C and above, white tin, or beta-tin, is metallic; below that temperature, the atomic structure of tin transitions, and the material becomes gray tin, or alpha-tin, which is semi-metallic. In thin films grown on a substrate such as indium antimonide (InSb), however, the transition temperature of tin goes up to 200°C, allowing alpha-tin to remain stable well above room temperature. Normally, alpha-tin's diamond-cubic crystal structure exhibits an ordinary semi-metallic phase – and the material has no common uses at the present time. In fact, gray tin can be problematic in many applications that involve tin – the so-called ‘tin pest’ problem involves the formation of gray tin that can cause disintegration of parts containing white tin. In their experiment, Xu and his colleagues engineered a strain in the material by growing layers of alpha-tin on a substrate of InSb, which has a slightly different lattice constant. "That lattice mismatch leads to strain, or compression, in the alpha-tin," Xu says. "It was believed that strain would open a band gap in gray tin and turn it into a TI. In a few recent studies researchers observed topological surface states in strained tin, but they didn't observe the strain-induced band gap because they were not able to access the conduction band. In this study, we used potassium doping and with this simple method were able to reach the conductance band. We were able to see the gapless and linear band dispersion that is the hallmark of a Dirac semi-metal. "This discovery is kind of unexpected. I decided to study the material because of its known TI phase. Once I dug into the experimental results and performed some theoretical calculations, what I found is that alpha-tin under a compressive strain is not an insulator, as had been thought. It turns out to be a Dirac semi-metal. Our calculations also show that it is only under a tensile strain that alpha-tin becomes a TI." Chiang believes these findings will open up new avenues of research. "Caizhi Xu's work illustrates that interesting new physics can still be found in simple common materials, such as gray tin, which has been known and studied for decades," he says. "It's clear from this study that strain engineering can open up many possibilities. My group is currently exploring a different way to apply strain, by mechanically stretching a sample. The strain will be uniaxial – along one direction only – and it will be tunable, but limited by sample breakage." Mankind has extracted and used tin in alloys since the Bronze Age, around 3000BC. Before the advent of aluminum cans, tin cans, which were actually steel lined with tin, were used for preserving food. This new discovery could allow alpha-tin to be a highly useful material in future technologies. "Potential applications of alpha-tin as a topological Dirac semi-metal could include taking advantage of its high carrier mobility to generate ultrafast electronic devices. Additionally, the giant magneto resistance could be useful in developing ultra-compact storage devices, like computer hard disks," suggests Xu. "Furthermore, this material could be a platform for further fundamental research related to optical properties, or to transport properties, including superconductivity. There is even potential that it could be used as a platform to realize Majorana fermions. I believe our new finding will be of interest to many physicists." This story is adapted from material from the University of Illinois at Urbana-Champaign, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.


News Article | April 17, 2017
Site: www.eurekalert.org

In a surprising new discovery, alpha-tin, commonly called gray tin, exhibits a novel electronic phase when its crystal structure is strained, putting it in a rare new class of 3D materials called topological Dirac semimetals (TDSs). Only two other TDS materials are known to exist, discovered as recently as 2013. Alpha-tin now joins this class as its only simple-element member. This discovery holds promise for novel physics and many potential applications in technology. The findings are the work of Caizhi Xu, a physics graduate student at the University of Illinois at Urbana-Champaign, working under U. of I. Professor Tai-Chang Chiang and in collaboration with scientists at the Advanced Light Source at the Lawrence Berkeley National Laboratory and six other institutions internationally. TDSs exhibit electronic properties akin to those of the now much-studied topological insulators (TIs) on their surfaces. The surfaces of TIs allow electrons to conduct freely like a metal, while the "bulk" or interior behaves as an insulator. The surface electrons behave as 2D massless spin-polarized Dirac fermions that are robust against non-magnetic impurities, which yields potential applications in spintronic devices and fault-tolerant quantum computing. By contrast, the bulk electrons in TDSs behave as massless Dirac fermions in all three dimensions, which leads to additional possibilities for novel physical behaviors. Xu explains, "TDSs are of profound interest to condensed matter physicists, primarily because they exhibit a number of novel physical properties, including ultrahigh carrier mobility, giant linear magnetoresistance, chiral anomaly, and novel quantum oscillations. Secondly, this class of materials can realize many interesting topological phases--under controlled conditions, the material can undergo phase transitions and can become a topological insulator, a Weyl semimetal, or a topological superconductor." Tin has two well-known allotropes: at 13.2? Celsius and above, white tin, or beta-tin, is metallic. Below that temperature, the atomic structure of tin transitions, and the material becomes gray tin, or alpha-tin, which is semi-metallic. In thin films grown on a substrate such as indium antimonide (InSb), however, the transition temperature of tin goes up to 200? C, which means alpha-tin remains stable well above room temperature. Normally, alpha-tin's diamond-cubic crystal structure exhibits an ordinary semi-metallic phase--and the material has no common uses at the present time. In fact, gray tin can be problematic in many applications that involve tin - the so-called "tin pest" problem is the formation of gray tin that causes disintegration of parts containing white tin. In their experiment, Xu et al. engineered a strain on the material by growing alpha-tin samples in layers on a substrate of another crystalline material, InSb, which has a slightly different lattice constant. "That lattice mismatch leads to strain, or compression, in the alpha-tin," Xu goes on to explain. "It was believed that strain would open a band gap in gray tin and turn it into a TI. In a few recent studies researchers observed topological surface states in strained tin, but they didn't observe the strain-induced band gap because they were not able to access the conduction band. In this study, we used potassium doping and with this simple method were able to reach the conductance band. We were able to see the gapless and linear band dispersion that is the hallmark of a Dirac semimetal. "This discovery is kind of unexpected. I decided to study the material because of its known TI phase. Once I dug into the experimental results and performed some theoretical calculations, what I found is that alpha-tin under a compressive strain is not an insulator, as had been thought. It turns out to be a Dirac semimetal. Our calculations also show that it is only under a tensile strain that alpha-tin becomes a TI." Chiang believes these findings will open new avenues of research: "Caizhi Xu's work illustrates that interesting new physics can still be found in simple common materials, such as gray tin, which has been known and studied for decades." "It's clear from this study that strain engineering can open up many possibilities," Chiang continues. "My group is currently exploring a different way to apply strain, by mechanically stretching a sample. The strain will be uniaxial--along one direction only--and it will be tunable, but limited by sample breakage." Mankind has extracted and used tin in alloys since the Bronze Age, c. 3000 BC. Before the advent of aluminum cans, tin cans, which were actually steel lined with tin, were used in preservation of food. With this discovery, alpha-tin may prove a highly useful material in future technologies. Xu shares, "Potential applications of alpha-tin as a topological Dirac semimetal could include taking advantage of its high carrier mobility to generate ultrafast electronic devices. Additionally, the giant magneto resistance could be useful in developing ultra-compact storage devices, like computer hard disks. "Furthermore, this material could be a platform for further fundamental research related to optical properties, or to transport properties, including superconductivity. There is even potential that it could be used as a platform to realize Majorana fermions. I believe our new finding will be of interest to many physicists." These findings are published in the April 4, 2017 Physical Review Letters, in the article "Elemental topological Dirac semimetal α-Sn on InSb," which is highlighted as a PRL Editor's Suggestion. This research is supported by the U. S. Department of Energy and the National Science Foundation, and by various international institutions. The samples were grown at Lawrence Berkeley National Laboratory's Advanced Light Source, which is supported by the U.S. Department of Energy.


News Article | April 28, 2017
Site: www.eurekalert.org

Bethesda, MD (April 28, 2017) -- The American Gastroenterological Association (AGA) Research Foundation is thrilled to award 52 researchers with research funding in the 2017 award year. "The AGA Research Foundation has a proven track record of funding young investigators who subsequently achieve great success in research. We are confident that the 2017 class will be no exception," said Robert S. Sandler, MD, MPH, AGAF, chair, AGA Research Foundation. "AGA is honored to invest in this year's award recipients and looks forward to seeing how each research project contributes to advancing the field of gastroenterology." The AGA Research Award Program serves to support talented investigators who are pursuing careers in digestive disease research. A grant from the AGA Research Foundation ensures that a major proportion of the recipient's time is protected for research. The awards program is made possible thanks to generous donors and funders contributing to the AGA Research Foundation. Show your support for GI research.https:/ Below are the 2017 AGA Research Foundation award recipients. To learn about upcoming research funding opportunities, visit http://www. . Shrinivas Bishu, MD, University of Michigan, Ann Arbor David Boone, PhD, Indiana University School of Medicine, Indianapolis Sarah Glover, DO, University of Florida, Gainesville Jennifer Lai, MD, MBA, The Regents of the University of California, San Francisco Jill Smith, MD, Georgetown University, Washington, D.C. Chandler Brown, Gallaudet University, Washington, D.C. Carlos Lodeiro, Texas Tech University Health Sciences Center El Paso Paul L. Foster School of Medicine Alyssa Murillo, University of Illinois at Chicago College of Medicine Kristeen Onyirioha, University of Texas San Antonio Health Sciences Center Gabriela Portilla Skerrett, San Juan Bautista School of Medicine, Puerto Rico Ray Ramirez, Eastern Virginia Medical School, Norfolk Rani Richardson, University of Pennsylvania, Philadelphia Nefertiti Tyehemba, State University of New York Upstate Medical University, Syracuse Elsie Ureta, California State University of Los Angeles Carlos Zavala, University of Illinois at Urbana-Champaign Edward Barnes, MD, MPH, University of North Carolina School of Medicine, Chapel Hill Daniel Duncan, MD, Boston Children's Hospital, MA Amy Engevik, PhD, Vanderbilt University, Nashville Tossapol Kerdsirichairat, MD, University of Michigan Health System, Ann Arbor Anne-Marie Overstreet, PhD, Indiana University School of Medicine, Indianapolis Shusuke Toden, PhD, Baylor University Medical Center/Baylor Research Institute, Houston Amy Tsou, MD, PhD, Boston Children's Hospital, MA Lavanya Viswanathan, MD, MS, Augusta University, GA Hongtao Wang, MD, PhD, Baylor College of Medicine and Texas Children's Hospital, Houston Lauren Cole, BS, University of Arizona College of Medicine, Phoenix Cindy Law, BSc, University of Ottawa, Canada Christopher Moreau, BS, University of Texas Health Science Center at San Antonio Satish Munigala, MBBS, MPH, St. Louis University, MO Rajiv Perinbasekar, MD, University of Maryland Medical Center, Baltimore Chung Sang Tse, MD, Mayo Clinic, Rochester, MN Anika Ullah, University of California, San Diego Kathy Williams, MS, Cooper Medical School of Rowan University, Camden, NJ Quan Zhou, MS, University of Michigan, Ann Arbor This year's honorees will be recognized during several AGA Research Foundation events at Digestive Disease Week® 2017, taking place May 6-9 in Chicago, IL. The American Gastroenterological Association is the trusted voice of the GI community. Founded in 1897, the AGA has grown to more than 16,000 members from around the globe who are involved in all aspects of the science, practice and advancement of gastroenterology. The AGA Institute administers the practice, research and educational programs of the organization.http://www. . Like AGA on Facebook.http://www. facebook. com/ amergastroassn> Follow us on Twitter @AmerGastroAssn.http://www. twitter. com/ amergastroassn> Check out our videos on YouTube.http://www. The AGA Research Foundation, formerly known as the Foundation for Digestive Health and Nutrition, is the cornerstone of AGA's effort to expand digestive disease research funding. Since 1984, the AGA, through its foundations, has provided more than $47 million in research grants to more than 870 scientists. The AGA Research Foundation serves as a bridge to the future of research in gastroenterology and hepatology by providing critical funding to advance the careers of young researchers between the end of training and the establishment of credentials that earn National Institutes of Health grants. Learn more about the AGA Research Foundation or make a contribution at http://www. .


As part of a partnership with APA and Harvard University's Graduate School of Design that brings planning directors from the nation's largest cities to the Lincoln Institute each year, Armando Carbonell, chair of the institute's Department of Planning and Urban Form, will moderate a panel, Big City Planning Directors on Equitable Redevelopment and Food Access, which will examine the economic, planning, and equity issues facing St. Louis, Milwaukee and other cities. The session, from 2:45 to 4:00 p.m. Monday May 8, will include a discussion of redevelopment surrounding the nearly $2 billion National Geospatial-Intelligence Agency facility planned in St. Louis near the site of the former Pruitt-Igoe housing complex. The Lincoln Institute's recently published book Nature and Cities: The Ecological Imperative in Urban Design and Planning will also make its debut at the conference. Featuring essays by leading landscape architects, planners, and urban designers, the book calls for integration of nature more fully into cities as the world urbanizes and the effects of climate change grow more severe. A complete list of the Lincoln Institute's sessions at the conference follows (all sessions at the Javits Convention Center): Fiscal Analysis, Municipal Finance, and the Economy, from 10:45 a.m. to noon Saturday May 6, kicking off the conference's fiscal track with a discussion of the pillars of municipal fiscal health, why they are relevant to the planners, and how cities and towns can make better land use decisions, with George "Mac" McCarthy of the Lincoln Institute and L. Carson Bise of TischlerBise (Room 1E07). Benchmarking and Municipal Fiscal Health, from 1 to 2:15 p.m. Saturday May 6, exploring ways planners can use the Fiscally Standardized Cities (FiSC) database to make meaningful budgetary comparisons across the largest 150 U.S., with Lincoln Institute Senior Research Analyst Adam Langley and Research Fellow Andrew Reschovsky, as well as Urban-Brookings Tax Policy Center Senior Fellow Tracy Gordon and Chicago Metropolitan Agency for Planning Deputy Executive Director for Planning Bob Dean (Room 1E08). Infrastructure Public Finance 101, from 4 to 5:15 p.m. Saturday May 6, surveying the financial avenues available to cities to pay for critical projects and the relationships between finance, project planning, and capital project administration, with Lourdes Germán of the Lincoln Institute and Susan Kendall of FirstSouthwest/Hilltop Securities (Room 1E15). Best Practices for Using Tax Incentives, from 1 to 2:15 p.m. Sunday May 7, detailing the costs and benefits of tax incentives, ways to make incentives more effective, the value of taking a regional approach, and alternative economic development strategies, with Edward Hill of Ohio State University, Daphne Kenyon of the Lincoln Institute, Greg LeRoy of Good Jobs First and Ronald Rakow of the City of Boston (Room E116). Nature and Cities: Ecological Planning and Design, from 1 to 2:15 p.m. Sunday May 7, looking at how ecological understanding can help planners respond to urban challenges like climate change with a focus on resilient urban design, with Timothy Beatley of the University of Virginia, Charlottesville, Armando Carbonell of the Lincoln Institute, Nina-Marie Lister of Ryerson University, and Forster Ndubisi of Texas A&M University (Room 1E10). Financing NYC's Hudson Yards, from 4 to 5:15 p.m. Sunday May 7, examining how the city of New York used the value of land to finance the multi-billion-dollar Hudson Yards infrastructure project on the city's Far West Side, with Lourdes Germán of the Lincoln Institute, and William Glasgall of the Volcker Alliance (Room 1A07). Applying Big Data to Small Projects, from 4 to 5:15 p.m. Sunday May 7, highlighting projects in California and Virginia to show how to gather and deploy big data to help achieve planning and transportation goals, with Amy Cotter of the Lincoln Institute, Chris McCahill of the State Smart Transportation Initiative, Chris Pangilinan of TransitCenter, and Laura Schewel of StreetLight Data (Room 1A08). Advancing Equity Analysis in Scenario Planning, from 7:30 to 8:45 a.m. Monday May 8, investigating how social equity concepts can be implemented  in planning practice using innovative scenario planning tools, with Colbey Brown of the Manhan Group, LLC, Arnab Chakraborty of the University of Illinois at Urbana-Champaign, Robert Goodspeed of the University of Michigan, Ann Arbor, Jennifer Minner of Cornell University, Peter Pollock of the Lincoln Institute, Alex Steinberger of Fregonese Associates, and Bev Wilson of the University of Illinois at Urbana-Champaign (Room  1A10). Big City Planning Directors on Equitable Redevelopment and Food Access, from 2:45 to 4:00 p.m. Monday May 8, confronting the economic, planning, and equity issues facing St. Louis, Milwaukee and other cities, with David Rouse of APA, Armando Carbonell of the Lincoln Institute, Vanessa Koster and Tim McCollow of the City of Milwaukee, Donald Roe of the City of St. Louis, Karen Shore of The Food Trust, and Toni Griffin of Urban Planning for the American City (Room 1E10). Scenario Analysis for Urban Planners, from 2:45 to 4 p.m. Monday May 8, on how scenario planning can acknowledge the inherent uncertainty of the future, using case studies that incorporated a wide range of voices, with Arnab Chakraborty of the University of Illinois at Urbana-Champaign, Amy Cotter of the Lincoln Institute, Janae Futrell of the city of Atlanta, and Kenneth Snyder of PlaceMatters (Room 1E07). Using the CIP to Make Plans Happen, from 4:15 to 5:30 p.m. Monday May 8, on how capital improvement plans can be used as vehicles to achieve planning goals, with Jean Gatza of the City of Boulder, Colorado, Julie Herlands of TischlerBise, and Peter Pollock of the Lincoln Institute (Room 1E09). Fiscal Policy and Land Use Interaction, from 9:30 to 10:45 a.m. Tuesday May 9, looking at how fiscal policy decisions affect land use outcomes and vice versa, and how to promote cooperation between city planners and public finance experts, with Amy Cotter of the Lincoln Institute, Julie Herlands of TischlerBise, Michael Pagano of the University of Illinois at Chicago, and Andrew Reschovsky of the Lincoln Institute (Room 1A06). Planning Directors' Perspectives on the Region, from 9:30 to 10:45 a.m. Tuesday May 9, providing a forum for planning directors form the New York City region to share the results of an all-day retreat, with Purnima Kapur of New York City, Peter Pollock of the Lincoln Institute and a number of planning directors from throughout the region (Room 1A21). Weighing the Future of Buyouts, from 9:30 to 10:45 a.m. Tuesday May 9, exploring the structure and function of buyout programs in flood-prone communities, and the improvements that can be made, with Robert Freudenberg of the Regional Plan Association and Deborah Hoffman of the County of Passaic, Totowa, New Jersey (Room 1E15). Improving Fiscal Impacts Analysis, from 9:30 to 10:45 a.m. Tuesday May 9, taking a deep dive into traditional methods used in fiscal impact analysis, critiques of traditional fiscal impact analysis, and alternative methodologies, with Peter Angelides, Daniel Miles, and Steven Nelson of Econsult Solutions, Inc. and Sidney Wong of Community Data Analytics (Room 1E14). The Lincoln Institute has been a longstanding partner with the American Planning Association's National Planning Conference, which is in its 109th year. The Lincoln Institute of Land Policy is an independent, nonpartisan organization whose mission is to help solve global economic, social, and environmental challenges to improve the quality of life through creative approaches to the use, taxation, and stewardship of land. To view the original version on PR Newswire, visit:http://www.prnewswire.com/news-releases/lincoln-institute-at-the-american-planning-association-2017-national-planning-conference-300446392.html


Patent
Beijing Apollo Ding Rong Solar Technology Co. and University of Illinois at Urbana - Champaign | Date: 2016-05-12

A method of manufacturing a photovoltaic structure includes forming a p-type semiconductor absorber layer containing a copper indium gallium selenide based material over a first electrode, forming a n-type cadmium sulfide layer over the p-type semiconductor absorber layer by sputtering in an ambient including hydrogen gas and oxygen gas, and forming a second electrode over the cadmium sulfide layer.


Patent
University of Illinois at Urbana - Champaign | Date: 2015-04-28

The present invention relates to the reduction of a symptom of an alcohol withdrawal state comprising administering a modulator of histone acetylation.


Chang H.-H.,University of Illinois at Urbana - Champaign
Psychometrika | Year: 2015

The paper provides a survey of 18 years' progress that my colleagues, students (both former and current) and I made in a prominent research area in Psychometrics-Computerized Adaptive Testing (CAT). We start with a historical review of the establishment of a large sample foundation for CAT. It is worth noting that the asymptotic results were derived under the framework of Martingale Theory, a very theoretical perspective of Probability Theory, which may seem unrelated to educational and psychological testing. In addition, we address a number of issues that emerged from large scale implementation and show that how theoretical works can be helpful to solve the problems. Finally, we propose that CAT technology can be very useful to support individualized instruction on a mass scale. We show that even paper and pencil based tests can be made adaptive to support classroom teaching.


Lopez-Pamies O.,University of Illinois at Urbana - Champaign
Journal of the Mechanics and Physics of Solids | Year: 2014

A microscopic field theory is developed with the aim of describing, explaining, and predicting the macroscopic response of elastic dielectric composites with two-phase particulate (periodic or random) microstructures under arbitrarily large deformations and electric fields. The central idea rests on the construction - via an iterated homogenization technique in finite electroelastostatics - of a specific but yet fairly general class of particulate microstructures which allow to compute exactly the homogenized response of the resulting composite materials. The theory is applicable to any choice of elastic dielectric behaviors (with possibly even or odd electroelastic coupling) for the underlying matrix and particles, and any choice of the one- and two-point correlation functions describing the microstructure. In spite of accounting for fine microscopic information, the required calculations amount to solving tractable first-order nonlinear (Hamilton-Jacobi-type) partial differential equations. As a first application of the theory, explicit results are worked out for the basic case of ideal elastic dielectrics filled with initially spherical particles that are distributed either isotropically or in chain-like formations and that are ideal elastic dielectrics themselves. The effects that the permittivity, stiffness, volume fraction, and spatial distribution of the particles have on the overall electrostrictive deformation (induced by the application of a uniaxial electric field) of the composite are discussed in detail. © 2013 Elsevier Ltd.


Braun P.V.,University of Illinois at Urbana - Champaign
Chemistry of Materials | Year: 2014

This Perspective overviews many of the developments in templated porous three-dimensional photonics, with a particular focus on functional architectures, and provides suggestions for future opportunities for research. A significant diversity of 3D structures is available today with characteristic dimensions appropriate for providing strong light-matter interactions, in no small part due to recent advances in 3D patterning techniques. However, the optical functionality of these structures has generally remained limited. Advances in materials chemistry have the opportunity to dramatically increase the function of templated 3D photonics, and a few examples of highly functional templated 3D photonics for sensing, solar energy harvesting, optical metamaterials, and light emission are presented as first examples of success. © 2013 American Chemical Society.


Biswas R.R.,University of Illinois at Urbana - Champaign
Physical Review Letters | Year: 2013

We consider Majorana fermions tunneling among an array of vortices in a 2D chiral p-wave superconductor or equivalent material. The amplitude for Majorana fermions to tunnel between a pair of vortices is found to necessarily depend on the background superconducting phase profile; it is found to be proportional to the sine of half the difference between the phases at the two vortices. Using this result we study tight-binding models of Majorana fermions in vortices arranged in triangular or square lattices. In both cases we find that the aforementioned phase-tunneling relationship leads to the creation of superlattices where the Majorana fermions form macroscopically degenerate localizable flat bands at zero energy, in addition to other dispersive bands. This finding suggests that tunneling processes in these vortex arrays do not change the energies of a finite fraction of Majorana fermions, contrary to previous expectation. The presence of flat Majorana bands, and hence less-than-expected decoherence in these vortex arrays, bodes well for the prospects of topological quantum computation with large numbers of Majorana states. © 2013 American Physical Society.


Layfield J.P.,University of Illinois at Urbana - Champaign | Hammes-Schiffer S.,University of Illinois at Urbana - Champaign
Chemical Reviews | Year: 2014

A study is conducted to demonstrate the theoretical treatments and simulation methods that have been developed to study hydrogen tunneling processes and to present examples of hydrogen tunneling in specific enzymatic and biomimetic systems. The ideas and concepts in this study have originated with assorted authors in various fields. The investigations have discussed the theoretical concepts and fundamental physical principles underlying hydrogen tunneling processes. The investigations characterize proton and hydride transfer, HAT, and EPT reactions in terms of electronic and vibrational nonadiabaticity and explain how to differentiate these types of reactions using electronic structure and semiclassical methods. The study also presents rate constant expressions for each type of reaction and discusses the approximations involved in the derivations of these expressions and the regimes in which they are valid.


Xiang Y.,University of Illinois at Urbana - Champaign | Lu Y.,University of Illinois at Urbana - Champaign
Nature Chemistry | Year: 2011

Portable, low-cost and quantitative detection of a broad range of targets at home and in the field has the potential to revolutionize medical diagnostics and environmental monitoring. Despite many years of research, very few such devices are commercially available. Taking advantage of the wide availability and low cost of the pocket-sized personal glucose meter - used worldwide by diabetes sufferers - we demonstrate a method to use such meters to quantify non-glucose targets, ranging from a recreational drug (cocaine, 3.4 μM detection limit) to an important biological cofactor (adenosine, 18 μM detection limit), to a disease marker (interferon-gamma of tuberculosis, 2.6 nM detection limit) and a toxic metal ion (uranium, 9.1 nM detection limit). The method is based on the target-induced release of invertase from a functional-DNA - invertase conjugate. The released invertase converts sucrose into glucose, which is detectable using the meter. The approach should be easily applicable to the detection of many other targets through the use of suitable functional-DNA partners (aptamers, DNAzymes or aptazymes). © 2011 Macmillan Publishers Limited. All rights reserved.


Dlott D.D.,University of Illinois at Urbana - Champaign
Annual Review of Physical Chemistry | Year: 2011

This review discusses new developments in shock compression science with a focus on molecular media. Some basic features of shock and detonation waves, nonlinear excitations that can produce extreme states of high temperature and high pressure, are described. Methods of generating and detecting shock waves are reviewed, especially those using tabletop lasers that can be interfaced with advanced molecular diagnostics. Newer compression methods such as shockless compression and precompression shock that generate states of cold dense molecular matter are discussed. Shock compression creates a metallic form of hydrogen, melts diamond, and makes water a superionic liquid with unique catalytic properties. Our understanding of detonations at the molecular level has improved a great deal as a result of advanced nonequilibrium molecular simulations. Experimental measurements of detailed molecular behavior behind a detonation front might be available soon using femtosecond lasers to produce nanoscale simulated detonation fronts. © 2011 by Annual Reviews. All rights reserved.


Motl R.W.,University of Illinois at Urbana - Champaign
Multiple Sclerosis Journal | Year: 2014

Supervised exercise training has substantial benefits for persons with multiple sclerosis (MS), yet 80% of those with MS do not meet recommended levels of moderate-to-vigorous physical activity (MVPA). This same problem persisted for decades in the general population of adults and prompted a paradigm shift away from "exercise training for fitness" toward "physical activity for health." The paradigm shift reflects a public health approach of promoting lifestyle physical activity through behavioral interventions that teach people the skills, techniques, and strategies based on established theories for modifying and self-regulating health behaviors. This paper describes: (a) the definitions of and difference between structured exercise training and lifestyle physical activity; (b) the importance and potential impact of the paradigm shift; (c) consequences of lifestyle physical activity in MS; and (d) behavioral interventions for changing lifestyle physical activity in MS. The paper introduces the "new kid on the MS block" with the hope that lifestyle physical activity might become an accepted partner alongside exercise training for inclusion in comprehensive MS care. © The Author(s) 2014.


Goh J.O.,University of Illinois at Urbana - Champaign
Aging and Disease | Year: 2011

Aging is associated with myriad changes in behavioral performance and brain structure and function. Given this complex interplay of brain and behavior, two streams of findings are reviewed here that show that aging is generally associated with dedifferentiated neural processes, and also changes in functional connectivity. This article considers an integrated view of how such age-related dedifferentiation of neural function and changes in functional connectivity are related, highlighting some recent findings on differences in small-world architecture in the functional connectivity of young and older adults. These findings suggest that both neural connectivity and the organization of these connections are important determinants of processing efficiency with aging that may be the underlying mechanisms for dedifferentiation. Thus, the evaluation of the neurocognitive effects of aging on functional connectivity provides an alternative framework that captures the behavioral and brain changes that are observed in cognitive aging.


Sreenivas R.S.,University of Illinois at Urbana - Champaign
IEEE Transactions on Automatic Control | Year: 2012

We first show that the existence, or nonexistence, of a supervisory policy that enforces liveness in an arbitrary Petri net (PN) is not semidecidable. Following this, we show that this is not the case if we restrict our attention to an arbitrary, partially controlled, free-choice Petri net (FCPN). Starting from the observation that the set of initial markings for which there is a supervisory policy that enforces liveness in a free-choice structure is right-closed, we present a string of observations that eventually lead to the conclusion that the existence of a supervisory policy that enforces liveness in an arbitrary FCPN is decidable. The paper concludes with some suggested directions for future research. © 2011 IEEE.


Strambeanu I.I.,University of Illinois at Urbana - Champaign | White M.C.,University of Illinois at Urbana - Champaign
Journal of the American Chemical Society | Year: 2013

The divergent synthesis of syn-1,2-aminoalcohol or syn-1,2-diamine precursors from a common terminal olefin has been accomplished using a combination of palladium(II) catalysis with Lewis acid cocatalysis. Palladium(II)/bis-sulfoxide catalysis with a silver triflate cocatalyst leads for the first time to anti-2-aminooxazolines (C-O) in good to excellent yields. Simple removal of the bis-sulfoxide ligand from this reaction results in a complete switch in reactivity to afford anti-imidazolidinone products (C-N) in good yields and excellent diastereoselectivities. Mechanistic studies suggest the divergent C-O versus C-N reactivity from a common ambident nucleophile arises due to a switch in mechanism from allylic C-H cleavage/functionalization to olefin isomerization/oxidative amination. © 2013 American Chemical Society.


Simple DNA repeats (trinucleotide repeats, micro- and minisatellites) are prone to expansion/contraction via formation of secondary structures during DNA synthesis. Such structures both inhibit replication forks and create opportunities for template-primer slippage, making these repeats unstable. Certain aspects of simple repeat instability, however, suggest additional mechanisms of replication inhibition dependent on the primary DNA sequence, rather than on secondary structure formation. I argue that expanded simple repeats, due to their lower DNA complexity, should transiently inhibit DNA synthesis by locally depleting specific DNA precursors. Such transient inhibition would promote formation of secondary structures and would stabilize these structures, facilitating strand slippage. Thus, replication problems at simple repeats could be explained by potentiated toxicity, where the secondary structure-driven repeat instability is enhanced by DNA polymerase stalling at the low complexity template DNA. © 2013 WILEY Periodicals, Inc.


Tang W.,University of Illinois at Urbana - Champaign | Van Der Donk W.A.,University of Illinois at Urbana - Champaign
Nature Chemical Biology | Year: 2013

The enterococcal cytolysin is a two-component lantibiotic of unknown structure with hemolytic activity that is important for virulence. We prepared cytolysin by coexpression of each precursor peptide with the synthetase CylM in Escherichia coli and characterized its structure. Unexpectedly, cytolysin is to our knowledge the first example of a lantibiotic containing lanthionine and methyllanthionine structures with different stereochemistries in the same peptide. The stereochemistry is determined by the sequence of the substrate peptide. © 2013 Nature America, Inc. All rights reserved.


Hammes-Schiffer S.,University of Illinois at Urbana - Champaign
Biochemistry | Year: 2013

This brief review analyzes the underlying physical principles of enzyme catalysis, with an emphasis on the role of equilibrium enzyme motions and conformational sampling. The concepts are developed in the context of three representative systems, namely, dihydrofolate reductase, ketosteroid isomerase, and soybean lipoxygenase. All of these reactions involve hydrogen transfer, but many of the concepts discussed are more generally applicable. The factors that are analyzed in this review include hydrogen tunneling, proton donor-acceptor motion, hydrogen bonding, pKa shifting, electrostatics, preorganization, reorganization, and conformational motions. The rate constant for the chemical step is determined primarily by the free energy barrier, which is related to the probability of sampling configurations conducive to the chemical reaction. According to this perspective, stochastic thermal motions lead to equilibrium conformational changes in the enzyme and ligands that result in configurations favorable for the breaking and forming of chemical bonds. For proton, hydride, and proton-coupled electron transfer reactions, typically the donor and acceptor become closer to facilitate the transfer. The impact of mutations on the catalytic rate constants can be explained in terms of the factors enumerated above. In particular, distal mutations can alter the conformational motions of the enzyme and therefore the probability of sampling configurations conducive to the chemical reaction. Methods such as vibrational Stark spectroscopy, in which environmentally sensitive probes are introduced site-specifically into the enzyme, provide further insight into these aspects of enzyme catalysis through a combination of experiments and theoretical calculations. © 2012 American Chemical Society.


Wang S.,University of Illinois at Urbana - Champaign
Annals of the Association of American Geographers | Year: 2010

Cyberinfrastructure (CI) integrates distributed information and communication technologies for coordinated knowledge discovery. The purpose of this article is to develop a CyberGIS framework for the synthesis of CI, geographic information systems (GIS), and spatial analysis (broadly including spatial modeling). This framework focuses on enabling computationally intensive and collaborative geographic problem solving. The article describes new trends in the development and use of CyberGIS while illustrating particular CyberGIS components. Spatial middleware glues CyberGIS components and corresponding services while managing the complexity of generic CI middleware. Spatial middleware, tailored to GIS and spatial analysis, is developed to capture important spatial characteristics of problems through the spatially explicit representation of computing, data, and communication intensity (collectively termed computational intensity), which enables GIS and spatial analysis to locate, allocate, and use CI resources effectively and efficiently. A CyberGIS implementation-GISolve-is developed to systematically integrate CI capabilities, including high-performance and distributed computing, data management and visualization, and virtual organization support. Currently, GISolve is deployed on the National Science Foundation TeraGrid, a key element of the U.S. and worldwide CI. A case study, motivated by an application in which geographic patterns of the impact of global climate change on large-scale crop yields are examined in the United States, focuses on assessing the computational performance of GISolve on resolving the computational intensity of a widely used spatial interpolation analysis that is conducted in a collaborative fashion. Computational experiments demonstrate that GISolve achieves a high-performance, distributed, and collaborative CyberGIS implementation. © 2010 by Association of American Geographers.


Huang R.H.,University of Illinois at Urbana - Champaign
Biochemistry | Year: 2012

In an RNA transcript, the 2′-OH group at the 3′-terminal nucleotide is unique as it is the only 2′-OH group that is adjacent to a 3′-OH group instead of a phosphate backbone. The 2′-OH group at the 3′-terminal nucleotide of certain RNAs is methylated in vivo, which is acheived by a methyltransferase named Hen1 that is mechanistically distinct from other known RNA 2′-O-methyltransferases. In eukaryotic organisms, 3′-terminal 2′-O-methylation of small RNAs stabilizes these small RNAs for RNA interference (RNAi). In bacteria, the same methylation during RNA repair results in repaired RNA resisting future damage at the site of repair. Although the chemistry performed by the eukaryotic and bacterial Hen1 is the same, the mechanisms of how RNA is stabilized as a result of the 3′-terminal 2′-O-methylation are different between the eukaryotic RNAi and the bacterial RNA repair. In this review, I will discuss the distribution of Hen1 in living organisms, the classification of Hen1 into four subfamilies, the structure and mechanism of Hen1 that allows it to conduct RNA 3′-terminal 2′-O-methylation, and the possible evolutionary origin of Hen1 present in bacterial and eukaryotic organisms. © 2012 American Chemical Society.


Oman T.J.,University of Illinois at Urbana - Champaign | Van Der Donk W.A.,University of Illinois at Urbana - Champaign
Nature Chemical Biology | Year: 2010

The avalanche of genomic information in the past decade has revealed that natural product biosynthesis using the ribosomal machinery is much more widespread than originally anticipated. Nearly all of these compounds are crafted through post-translational modifications of a larger precursor peptide that often contains the marching orders for the biosynthetic enzymes. We review here the available information for how the peptide sequences in the precursors govern the post-translational tailoring processes for several classes of natural products. In addition, we highlight the great potential these leader peptide-directed biosynthetic systems offer for engineering conformationally restrained and pharmacophore-rich products with structural diversity that greatly expands the proteinogenic repertoire. © 2010 Nature America, Inc. All rights reserved.


Hwang H.,University of Illinois at Urbana - Champaign | Myong S.,University of Illinois at Urbana - Champaign
Chemical Society Reviews | Year: 2014

Single molecule studies of protein-nucleic acid interactions shed light on molecular mechanisms and kinetics involved in protein binding, translocation, and unwinding of DNA and RNA substrates. In this review, we provide an overview of a single molecule fluorescence method, termed "protein induced fluorescence enhancement" (PIFE). Unlike FRET where two dyes are required, PIFE employs a single dye attached to DNA or RNA to which an unlabeled protein is applied. We discuss both ensemble and single molecule studies in which PIFE was utilized. © 2014 The Royal Society of Chemistry.


Blehm B.H.,University of Illinois at Urbana - Champaign | Selvin P.R.,University of Illinois at Urbana - Champaign
Chemical Reviews | Year: 2014

The review describes experimental systems at multiple levels of complexity, including single-motor-type in vitro assays, multimotor in vitro assays, purified-organelle in vitro assays, and finally in vivo cellular assays. The simplest level of complexity is a single motor with a cargo or label attached and a microtubule track in an in vitro environment. This has been the predominant type of experiment in the study of molecular motors. Adding in accessory proteins and parts of the transport complex, such as dynactin, is the next level of complexity. From the wide variety of in vivo optical trapping results, the different kinesin-dynein transport systems present quite a bit of complexity. Dynein apparently is dragged behind kinesin during some plus-end directed transport, whereas kinesin routinely releases to allow unhindered minus-end-directed transport. More complex systems, such as systems with more motor types present, or other specialized types of transport promise to add more complex regulatory mechanisms.


Orlean P.,University of Illinois at Urbana - Champaign
Genetics | Year: 2012

The wall gives a Saccharomyces cerevisiae cell its osmotic integrity; defines cell shape during budding growth, mating, sporulation, and pseudohypha formation; and presents adhesive glycoproteins to other yeast cells. The wall consists of β1,3- and β 1,6-glucans, a small amount of chitin, and many different proteins that may bear N- and O-linked glycans and a glycolipid anchor. These components become cross-linked in various ways to form higher-order complexes. Wall composition and degree of cross-linking vary during growth and development and change in response to cell wall stress. This article reviews wall biogenesis in vegetative cells, covering the structure of wall components and how they are cross-linked; the biosynthesis of N- and O-linked glycans, glycosylphosphatidylinositol membrane anchors, β1,3- and β1,6-linked glucans, and chitin; the reactions that cross-link wall components; and the possible functions of enzymatic and nonenzymatic cell wall proteins. © 2012 the Genetics Society of America.


Knerr P.J.,University of Illinois at Urbana - Champaign | Van Der Donk W.A.,University of Illinois at Urbana - Champaign
Annual Review of Biochemistry | Year: 2012

Aided by genome-mining strategies, knowledge of the prevalence and diversity of ribosomally synthesized natural products (RNPs) is rapidly increasing. Among these are the lantipeptides, posttranslationally modified peptides containing characteristic thioether cross-links imperative for bioactivity and stability. Though this family was once thought to be a limited class of antimicrobial compounds produced by gram-positive bacteria, new insights have revealed a much larger diversity of activity, structure, biosynthetic machinery, and producing organisms than previously appreciated. Detailed investigation of the enzymes responsible for installing the posttranslational modifications has resulted in improved in vivo and in vitro engineering systems focusing on enhancement of the therapeutic potential of these compounds. Although dozens of new lantipeptides have been isolated in recent years, bioinformatic analyses indicate that many hundreds more await discovery owing to the widespread frequency of lantipeptide biosynthetic machinery in bacterial genomes. © 2012 by Annual Reviews. All rights reserved.


Van Der Donk W.A.,University of Illinois at Urbana - Champaign
Journal of the American Chemical Society | Year: 2012

Methylphosphonate synthase is a non-heme iron-dependent oxygenase that converts 2-hydroxyethylphosphonate (2-HEP) to methylphosphonate. On the basis of experiments with two enantiomers of a substrate analog, 2- hydroxypropylphosphonate, catalysis is proposed to commence with stereospecific abstraction of the pro-S hydrogen on C2 of the substrate. Experiments with isotopologues of 2-HEP indicate stereospecific hydrogen transfer of the pro-R hydrogen at C2 of the substrate to the methyl group of methylphosphonate. Kinetic studies with these substrate isotopologues reveal that neither hydrogen transfer is rate limiting under saturating substrate conditions. A mechanism is proposed that is consistent with the available data. © 2012 American Chemical Society.


Wong C.-H.,University of Illinois at Urbana - Champaign | Zimmerman S.C.,University of Illinois at Urbana - Champaign
Chemical Communications | Year: 2013

The concept of orthogonality has been applied to many areas of chemistry, ranging from wave functions to chromatography. But it was Barany and Merrifield's orthogonal protecting group strategy that paved the way for solid phase peptide syntheses, other important classes of biomaterials such as oligosaccharides and oligonucleotides, and ultimately to a term in widespread usage that is focused on chemical reactivity and binding selectivity. The orthogonal protection strategy has been extended to the development of orthogonal activation, and recently the click reaction, for streamlining organic synthesis. The click reaction and its variants are considered orthogonal as the components react together in high yield and in the presence of many other functional groups. Likewise, supramolecular building blocks can also be orthogonal, thereby enabling programmed self-assembly, a superb strategy to create complex architectures. Overall, orthogonal reactions and supramolecular interactions have dramatically improved the syntheses, the preparation of functional materials, and the self-assembly of nanoscale structures. This journal is © The Royal Society of Chemistry 2013.


Bhargava R.,University of Illinois at Urbana - Champaign
Applied Spectroscopy | Year: 2012

Infrared (IR) spectroscopic imaging seemingly matured as a technology in the mid-2000s, with commercially successful instrumentation and reports in numerous applications. Recent developments, however, have transformed our understanding of the recorded data, provided capability for new instrumentation, and greatly enhanced the ability to extract more useful information in less time. These developments are summarized here in three broad areas- data recording, interpretation of recorded data, and information extraction-and their critical review is employed to project emerging trends. Overall, the convergence of selected components from hardware, theory, algorithms, and applications is one trend. Instead of similar, general-purpose instrumentation, another trend is likely to be diverse and applicationtargeted designs of instrumentation driven by emerging component technologies. The recent renaissance in both fundamental science and instrumentation will likely spur investigations at the confluence of conventional spectroscopic analyses and optical physics for improved data interpretation. While chemometrics has dominated data processing, a trend will likely lie in the development of signal processing algorithms to optimally extract spectral and spatial information prior to conventional chemometric analyses. Finally, the sum of these recent advances is likely to provide unprecedented capability in measurement and scientific insight, which will present new opportunities for the applied spectroscopist.


Oldfield E.,University of Illinois at Urbana - Champaign | Lin F.-Y.,University of Illinois at Urbana - Champaign
Angewandte Chemie - International Edition | Year: 2012

Terpenes are the largest class of small-molecule natural products on earth, and the most abundant by mass. Here, we summarize recent developments in elucidating the structure and function of the proteins involved in their biosynthesis. There are six main building blocks or modules (α, β, γ, δ, ε, and ζ) that make up the structures of these enzymes: the αα and αδ head-to-tail trans-prenyl transferases that produce trans-isoprenoid diphosphates from C 5 precursors; the ε head-to-head prenyl transferases that convert these diphosphates into the tri- and tetraterpene precursors of sterols, hopanoids, and carotenoids; the βγ di- and triterpene synthases; the ζ head-to-tail cis-prenyl transferases that produce the cis-isoprenoid diphosphates involved in bacterial cell wall biosynthesis; and finally the α, αβ, and αβγ terpene synthases that produce plant terpenes, with many of these modular enzymes having originated from ancestral α and β domain proteins. We also review progress in determining the structure and function of the two 4Fe-4S reductases involved in formation of the C 5 diphosphates in many bacteria, where again, highly modular structures are found. Natural building blocks: Recent progress has been achieved in determining the structure, function, and inhibition of the enzymes responsible for the formation of terpenes and isoprenoids. Most of these enzymes contain combinations of α-, β-, γ-, δ-, ε-, and/or ζ-domain structures that in many cases are fused to form modular proteins. Gene fusion, exon loss, and recombination are thought to play major roles in the genesis of these enzymes. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Saini S.,University of Illinois at Urbana - Champaign
PLoS pathogens | Year: 2010

Salmonella enterica serovar Typhimurium is a common food-borne pathogen that induces inflammatory diarrhea and invades intestinal epithelial cells using a type three secretion system (T3SS) encoded within Salmonella pathogenicity island 1 (SPI1). The genes encoding the SPI1 T3SS are tightly regulated by a network of interacting transcriptional regulators involving three coupled positive feedback loops. While the core architecture of the SPI1 gene circuit has been determined, the relative roles of these interacting regulators and associated feedback loops are still unknown. To determine the function of this circuit, we measured gene expression dynamics at both population and single-cell resolution in a number of SPI1 regulatory mutants. Using these data, we constructed a mathematical model of the SPI1 gene circuit. Analysis of the model predicted that the circuit serves two functions. The first is to place a threshold on SPI1 activation, ensuring that the genes encoding the T3SS are expressed only in response to the appropriate combination of environmental and cellular cues. The second is to amplify SPI1 gene expression. To experimentally test these predictions, we rewired the SPI1 genetic circuit by changing its regulatory architecture. This enabled us to directly test our predictions regarding the function of the circuit by varying the strength and dynamics of the activating signal. Collectively, our experimental and computational results enable us to deconstruct this complex circuit and determine the role of its individual components in regulating SPI1 gene expression dynamics.


Saini S.,University of Illinois at Urbana - Champaign
PLoS pathogens | Year: 2010

Salmonella enterica serovar Typhimurium is a common food-borne pathogen that induces inflammatory diarrhea and invades intestinal epithelial cells using a type three secretion system (T3SS) encoded within Salmonella pathogenicity island 1 (SPI1). The genes encoding the SPI1 T3SS are tightly regulated by a network of interacting transcriptional regulators involving three coupled positive feedback loops. While the core architecture of the SPI1 gene circuit has been determined, the relative roles of these interacting regulators and associated feedback loops are still unknown. To determine the function of this circuit, we measured gene expression dynamics at both population and single-cell resolution in a number of SPI1 regulatory mutants. Using these data, we constructed a mathematical model of the SPI1 gene circuit. Analysis of the model predicted that the circuit serves two functions. The first is to place a threshold on SPI1 activation, ensuring that the genes encoding the T3SS are expressed only in response to the appropriate combination of environmental and cellular cues. The second is to amplify SPI1 gene expression. To experimentally test these predictions, we rewired the SPI1 genetic circuit by changing its regulatory architecture. This enabled us to directly test our predictions regarding the function of the circuit by varying the strength and dynamics of the activating signal. Collectively, our experimental and computational results enable us to deconstruct this complex circuit and determine the role of its individual components in regulating SPI1 gene expression dynamics.


Nedic A.,University of Illinois at Urbana - Champaign
IEEE Transactions on Automatic Control | Year: 2011

We consider a distributed multi-agent network system where each agent has its own convex objective function, which can be evaluated with stochastic errors. The problem consists of minimizing the sum of the agent functions over a commonly known constraint set, but without a central coordinator and without agents sharing the explicit form of their objectives. We propose an asynchronous broadcast-based algorithm where the communications over the network are subject to random link failures. We investigate the convergence properties of the algorithm for a diminishing (random) stepsize and a constant stepsize, where each agent chooses its own stepsize independently of the other agents. Under some standard conditions on the gradient errors, we establish almost sure convergence of the method to an optimal point for diminishing stepsize. For constant stepsize, we establish some error bounds on the expected distance from the optimal point and the expected function value. We also provide numerical results. © 2006 IEEE.


Zayed A.,York University | Robinson G.E.,University of Illinois at Urbana - Champaign
Annual Review of Genetics | Year: 2012

Behavior is a complex phenotype that is plastic and evolutionarily labile. The advent of genomics has revolutionized the field of behavioral genetics by providing tools to quantify the dynamic nature of brain gene expression in relation to behavioral output. The honey bee Apis mellifera provides an excellent platform for investigating the relationship between brain gene expression and behavior given both the remarkable behavioral repertoire expressed by members of its intricate society and the degree to which behavior is influenced by heredity and the social environment. Here, we review a linked series of studies that assayed changes in honey bee brain transcriptomes associated with natural and experimentally induced changes in behavioral state. These experiments demonstrate that brain gene expression is closely linked with behavior, that changes in brain gene expression mediate changes in behavior, and that the association between specific genes and behavior exists over multiple timescales, from physiological to evolutionary. © 2012 by Annual Reviews.


Kuzminov A.,University of Illinois at Urbana - Champaign
Molecular Microbiology | Year: 2013

Summary: In both eukaryotes and prokaryotes, chromosomal DNA undergoes replication, condensation-decondensation and segregation, sequentially, in some fixed order. Other conditions, like sister-chromatid cohesion (SCC), may span several chromosomal events. One set of these chromosomal transactions within a single cell cycle constitutes the 'chromosome cycle'. For many years it was generally assumed that the prokaryotic chromosome cycle follows major phases of the eukaryotic one: -replication-condensation-segregation-(cell division)-decondensation-, with SCC of unspecified length. Eventually it became evident that, in contrast to the strictly consecutive chromosome cycle of eukaryotes, all stages of the prokaryotic chromosome cycle run concurrently. Thus, prokaryotes practice 'progressive' chromosome segregation separated from replication by a brief SCC, and all three transactions move along the chromosome at the same fast rate. In other words, in addition to replication forks, there are 'segregation forks' in prokaryotic chromosomes. Moreover, the bulk of prokaryotic DNA outside the replication-segregation transition stays compacted. I consider possible origins of this concurrent replication-segregation and outline the 'nucleoid administration' system that organizes the dynamic part of the prokaryotic chromosome cycle. © 2013 John Wiley & Sons Ltd.


Sun J.,University of Illinois at Urbana - Champaign
Nature communications | Year: 2013

Protein functions are largely affected by their conformations. This is exemplified in proteins containing modular domains. However, the evolutionary dynamics that define and adapt the conformation of such modular proteins remain elusive. Here we show that cis-interactions between the C-terminal phosphotyrosines and SH2 domain within the protein tyrosine phosphatase Shp2 can be tuned by an adaptor protein, Grb2. The competitiveness of two phosphotyrosines, namely pY542 and pY580, for cis-interaction with the same SH2 domain is governed by an antagonistic combination of contextual amino acid sequence and position of the phosphotyrosines. Specifically, pY580 with the combination of a favourable position and an adverse sequence has an overall advantage over pY542. Swapping the sequences of pY542 and pY580 results in one dominant form of cis-interaction and subsequently inhibits the trans-regulation by Grb2. Thus, the antagonistic combination of sequence and position may serve as a basic design principle for proteins with tunable conformations.


Tse E.C.M.,University of Illinois at Urbana - Champaign
Nature Materials | Year: 2016

Many chemical and biological processes involve the transfer of both protons and electrons. The complex mechanistic details of these proton-coupled electron transfer (PCET) reactions require independent control of both electron and proton transfer. In this report, we make use of lipid-modified electrodes to modulate proton transport to a Cu-based catalyst that facilitates the O2 reduction reaction (ORR), a PCET process important in fuel cells and O2 reduction enzymes. By quantitatively controlling the kinetics of proton transport to the catalyst, we demonstrate that undesired side products such as H2O2 and O2 - arise from a mismatch between proton and electron transfer rates. Whereas fast proton kinetics induce H2O2 formation and sluggish proton flux produces O2 -, proton transfer rates commensurate with O–O bond breaking rates ensure that only the desired H2O product forms. This fundamental insight aids in the development of a comprehensive framework for understanding the ORR and PCET processes in general. © 2016 Nature Publishing Group


Mcmillen D.P.,University of Illinois at Urbana - Champaign
Journal of Regional Science | Year: 2012

Though standard spatial econometric models may be useful for specification testing, they rely heavily on a parametric structure that is highly sensitive to model misspecification. The commonly used spatial AR model is a form of spatial smoothing with a structure that closely resembles a semiparametric model. Nonparametric and semiparametric models are generally a preferable approach for more descriptive spatial analysis. Estimated population density functions illustrate the differences between the spatial AR model and nonparametric approaches to data smoothing. A series of Monte Carlo experiments demonstrates that nonparametric predicted values and marginal effect estimates are much more accurate then spatial AR models when the contiguity matrix is misspecified. © 2012, Wiley Periodicals, Inc.


Silverman S.K.,University of Illinois at Urbana - Champaign
Accounts of Chemical Research | Year: 2015

ConspectusCatalysis is a fundamental chemical concept, and many kinds of catalysts have considerable practical value. Developing entirely new catalysts is an exciting challenge. Rational design and screening have provided many new small-molecule catalysts, and directed evolution has been used to optimize or redefine the function of many protein enzymes. However, these approaches have inherent limitations that prompt the pursuit of different kinds of catalysts using other experimental methods.Nature evolved RNA enzymes, or ribozymes, for key catalytic roles that in modern biology are limited to phosphodiester cleavage/ligation and amide bond formation. Artificial DNA enzymes, or deoxyribozymes, have great promise for a broad range of catalytic activities. They can be identified from unbiased (random) sequence populations as long as the appropriate in vitro selection strategies can be implemented for their identification. Notably, in vitro selection is different in key conceptual and practical ways from rational design, screening, and directed evolution. This Account describes the development by in vitro selection of DNA catalysts for many different kinds of covalent modification reactions of peptide and protein substrates, inspired in part by our earlier work with DNA-catalyzed RNA ligation reactions.In one set of studies, we have sought DNA-catalyzed peptide backbone cleavage, with the long-term goal of artificial DNA-based proteases. We originally anticipated that amide hydrolysis should be readily achieved, but in vitro selection instead surprisingly led to deoxyribozymes for DNA phosphodiester hydrolysis; this was unexpected because uncatalyzed amide bond hydrolysis is 105-fold faster. After developing a suitable selection approach that actively avoids DNA hydrolysis, we were able to identify deoxyribozymes for hydrolysis of esters and aromatic amides (anilides). Aliphatic amide cleavage remains an ongoing focus, including via inclusion of chemically modified DNA nucleotides in the catalyst, which we have recently found to enable this cleavage reaction. In numerous other efforts, we have investigated DNA-catalyzed peptide side chain modification reactions. Key successes include nucleopeptide formation (attachment of oligonucleotides to peptide side chains) and phosphatase and kinase activities (removal and attachment of phosphoryl groups to side chains).Through all of these efforts, we have learned the importance of careful selection design, including the frequent need to develop specific "capture" reactions that enable the selection process to provide only those DNA sequences that have the desired catalytic functions. We have established strategies for identifying deoxyribozymes that accept discrete peptide and protein substrates, and we have obtained data to inform the key choice of random region length at the outset of selection experiments. Finally, we have demonstrated the viability of modular deoxyribozymes that include a small-molecule-binding aptamer domain, although the value of such modularity is found to be minimal, with implications for many selection endeavors.Advances such as those summarized in this Account reveal that DNA has considerable catalytic abilities for biochemically relevant reactions, specifically including covalent protein modifications. Moreover, DNA has substantially different, and in many ways better, characteristics than do small molecules or proteins for a catalyst that is obtained "from scratch" without demanding any existing information on catalyst structure or mechanism. Therefore, prospects are very strong for continued development and eventual practical applications of deoxyribozymes for peptide and protein modification. © 2015 American Chemical Society.


Ozawa T.,University of Illinois at Urbana - Champaign | Baym G.,University of Illinois at Urbana - Champaign
Physical Review Letters | Year: 2012

We study the stability of Bose condensates with Rashba-Dresselhaus spin-orbit coupling in three dimensions against quantum and thermal fluctuations. The ground state depletion of the plane-wave condensate due to quantum fluctuations is, as we show, finite, and therefore the condensate is stable. We also calculate the corresponding shift of the ground state energy. Although the system cannot condense in the absence of interparticle interactions, by estimating the number of excited particles we show that interactions stabilize the condensate even at nonzero temperature. Unlike in the usual Bose gas, the normal phase is not kinematically forbidden at any temperature; calculating the free energy of the normal phase at finite temperature, and comparing with the free energy of the condensed state, we infer that generally the system is condensed at zero temperature, and undergoes a transition to normal at nonzero temperature. © 2012 American Physical Society.


Bergamaschi A.,University of Illinois at Urbana - Champaign | Katzenellenbogen B.S.,University of Illinois at Urbana - Champaign
Oncogene | Year: 2012

Many estrogen receptor (ER)-positive breast cancers respond well initially to endocrine therapies, but often develop resistance during treatment with selective ER modulators (SERMs) such as tamoxifen. We have reported that the 14-3-3ζ family member and conserved protein, 14-3-3ζ, is upregulated by tamoxifen and that high expression correlated with an early time to disease recurrence. However, the mechanism by which tamoxifen upregulates 14-3-3ζ and may promote the development of endocrine resistance is not known. Our findings herein reveal that the tamoxifen upregulation of 14-3-3ζ results from its ability to rapidly downregulate microRNA (miR)-451 that specifically targets 14-3-3ζ. The levels of 14-3-3ζ and miR-451 were inversely correlated, with 14-3-3ζ being elevated and miR-451 being at a greatly reduced level in tamoxifen-resistant breast cancer cells. Of note, downregulation of miR-451 was selectively elicited by tamoxifen but not by other SERMs, such as raloxifene or ICI182,780 (Fulvestrant). Increasing the level of miR-451 by overexpression, which decreased 14-3-3ζ, suppressed cell proliferation and colony formation, markedly reduced activation of HER2, EGFR and MAPK signaling, increased apoptosis, and, importantly, restored the growth-inhibitory effectiveness of SERMs in endocrine-resistant cells. Opposite effects were elicited by miR-451 knockdown. Thus, we identify tamoxifen downregulation of miR-451, and consequent elevation of the key survival factor 14-3-3ζ, as a mechanistic basis of tamoxifen-associated development of endocrine resistance. These findings suggest that therapeutic approaches to increase expression of this tumor suppressor-like miR should be considered to downregulate 14-3-3ζ and enhance the effectiveness of endocrine therapies. Furthermore, the selective ability of the SERM tamoxifen but not raloxifene to regulate miR-451 and 14-3-3ζ may assist in understanding differences in their activities, as seen in the STAR (Study of Tamoxifen and Raloxifene) breast cancer prevention trial and in other clinical trials. © 2012 Macmillan Publishers Limited All rights reserved.


Boppart S.A.,University of Illinois at Urbana - Champaign | Richards-Kortum R.,Rice University
Science Translational Medicine | Year: 2014

Leveraging advances in consumer electronics and wireless telecommunications, low-cost, portable optical imaging devices have the potential to improve screening and detection of disease at the point of care in primary health care settings in both low- and high-resource countries. Similarly, real-time optical imaging technologies can improve diagnosis and treatment at the point of procedure by circumventing the need for biopsy and analysis by expert pathologists, who are scarce in developing countries. Although many optical imaging technologies have been translated from bench to bedside, industry support is needed to commercialize and broadly disseminate these from the patient level to the population level to transform the standard of care. This review provides an overview of promising optical imaging technologies, the infrastructure needed to integrate them into widespread clinical use, and the challenges that must be addressed to harness the potential of these technologies to improve health care systems around the world. © 2014, American Association for the Advancement of Science. All rights reserved.


Zong X.,University of Illinois at Urbana - Champaign
RNA biology | Year: 2011

The mammalian genome harbors a large number of long non-coding RNAs (lncRNAs) that do not code for proteins, but rather they exert their function directly as RNA molecules. LncRNAs are involved in executing several vital cellular functions. They facilitate the recruitment of proteins to specific chromatin sites, ultimately regulating processes like dosage compensation and genome imprinting. LncRNAs are also known to regulate nucleocytoplasmic transport of macromolecules. A large number of the regulatory lncRNAs are retained within the cell nucleus and constitute a subclass termed nuclear-retained RNAs (nrRNAs). NrRNAs are speculated to be involved in crucial gene regulatory networks, acting as structural scaffolds of subnuclear domains. NrRNAs modulate gene expression by influencing chromatin modification, transcription and post-transcriptional gene processing. The cancer-associated Metastasis-associated lung adenocarcinoma transcript1 (MALAT1) is one such long nrRNA that regulates pre-mRNA processing in mammalian cells. Thus far, our understanding about the roles played by nrRNAs and their relevance in disease pathways is only 'a tip of an iceberg'. It will therefore be crucial to unravel the functions for the vast number of long nrRNAs, buried within the complex mine of the human genome.

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